The frequent, heavy rains in certain areas of the state have resulted in the appearance of mushrooms in home lawns and landscape beds. Although mushrooms are often spectacular in size and color, most are relatively harmless to plant life. Some of these mushrooms are associated with arc-like or circular patterns in turfgrass called fairy rings. The ring pattern is caused by the outward growth of fungal mycelium. The mycelium forms a dense, mat-like structure in the soil that decomposes organic matter. This decomposition releases nitrate into the soil, which in turn stimulates the growth of the grass at the outer portion of the ring. This results in a dark green appearance of the grass at the margin of the ring.  Unfortunately, the thick fungal mat formed by the fungus interferes with water infiltration. The fungus also may release certain byproducts that are toxic to the turf. This may lead to dieback of the turf close to the ring. Therefore, in some cases the ring is evidenced by a darker green color and in others, by a brown ring with the outside edge being darker green than the rest of the turf.
        
Fairy rings are difficult to control. You can sometimes eliminate the ring by digging to a depth of 6 to 12 inches and 12 inches wide on both sides of the ring, refilling the hole with non-infested soil. Or you can try to mask the symptoms by fertilizing the rest of the lawn so that it is as dark green as the ring. This often isn't a good idea because it tends to promote other turf problems. Commercial people can use certain fungicides to control fairy rings but these products are not available to homeowners.   See http://www.ksre.ksu.edu/bookstore/pubs/EP155.pdf  for more info on these fungicides.
        
Some mushrooms in lawns are not associated with fairy rings. These may be mycorrhizal (symbiotic association with tree roots) or saprophytic (live on dead organic matter such as wood, etc.) in the soil. Because some of these mushrooms are beneficial, you don't really want to kill them. Besides, a fungicide spray to the mushroom itself does little good. Remember the mushroom is simply the fruiting structure of the organism. Most of the fungus is below ground and inaccessible to the chemical. If mushrooms are a nuisance, pick them and dispose of them as soon as they appear. Remove sources of large organic debris from the soil. Also, mushrooms tend to go away as soil dries. Patience may be the best control. Some of the mushrooms in the lawn are edible, but others are poisonous. Never eat mushrooms unless you are sure of their identity. (Ward Upham)

May is an excellent time to fertilize cool-season lawns such as tall fescue and Kentucky bluegrass if they will be irrigated throughout the summer. Non-irrigated lawns often go through a period of summer dormancy because of drought and do not need this fertilization.
 
May is a good time to fertilize because the springtime flush of growth characteristic of these grasses has tapered off, so the fertilizer you apply will be less likely to cause excessive shoot growth than if you fertilized at a full rate in April. Slow-release nitrogen sources are ideal. These nitrogen sources promote controlled growth, which is desirable as the stressful summer weather approaches. Relatively few fertilizers available to the homeowner supply ALL of the nitrogen in the slowly available form. But one such product that is widely available is Milorganite. Other such products available in the retail market include cottonseed meal, alfalfa-based fertilizers, and any other products derived from plants or animals. (Bloodmeal is an exception, and contrary to popular belief, the nitrogen it supplies is quickly available.) These products are all examples of natural organic fertilizers. They typically contain less than 10 percent nitrogen by weight, so compared to most synthetic fertilizers, more product must be applied to get the same amount of nitrogen. Translation: they are more expensive! Apply enough to give the lawn one pound of nitrogen per 1,000 square feet. For example, if the fertilizer is 6 percent nitrogen by weight, you will need to apply almost 17 pounds of fertilizer product per 1,000 square feet. Summer lawn fertilizers that contain at least a portion of the nitrogen as slow-release are fine to use as well. Be sure to follow label directions. If cost is prohibitive, you can use the less expensive quick-release (i.e., soluble) sources, but split the application into two doses as follows: apply enough to give the lawn 0.5 lb nitrogen per 1,000 square feet in May and again in early June. (Ward Upham)

Peach leaf curl is a fungus disease that causes developing peach leaves to become puckered and distorted and show a reddish-green hue. A similar disease called plum pocket may develop on American and sand hill plums. Plum pocket results in formation of distorted, light green, bladder-shaped fruit. Asian and European plums are not susceptible to the local strain of plum pocket. Unfortunately, it is too late to control these diseases with fungicides this year.
 
Trees that are severely infected with peach leaf curl are likely to lose many leaves. If trees are healthy, new leaves will grow. Indicators of a healthy tree are large, deep green leaves and last year's growth being at least 18 to 24 inches long. If these tree vigor indicators are not present, especially if there was only 12 inches or less of growth last year, then a fertilizer application would be helpful.
 
The fertilizer should be spread on the soil under the branch area. Apply 1 and 1/3 to 2 cups of a 13-13-13 fertilizer under the branch area. If a soil test indicates that only nitrogen is needed, use 1/3 to 1½ cups of nitrate of soda (16-0-0) instead of the 13-13-13. You may also substitute a high nitrogen fertilizer such as a 27-3-4, 30-5-4 or something similar for the 13-13-13, but use only half the amount used for nitrate of soda. The sooner fertilizer is applied, the more immediate benefit it will have in promoting new leaf growth. Both peach leaf curl and plum pocket can be controlled with a single fungicide application applied this fall after leaf drop or early next spring before bud swell.
 
Effective fungicides include Bordeaux mixture and chlorothalonil (Bravo, Daconil and others). Be sure to cover the entire tree including the bark and trunk. (Ward Upham)

Two of the common pesticides used in fruit tree sprays are malathion (for insects) and captan (for diseases). Unfortunately, both of these products are subject to alkaline hydrolysis. This is a process whereby certain pesticides will break down when mixed with high pH water. So let’s say you mix up your spray mixture by adding malathion and captan to 5 gallons of water. If that water has a pH of 7, the captan will break down so that only half of it will still be present in 8 hours.
 
However, if the water you use has a pH of 10, half the captan will break down in 2 minutes. Malathion isn’t nearly as sensitive but still will break down under high pH conditions though it is stable at a pH between 5 and 7. Note that alkaline hydrolysis does not affect all pesticides. Captan is the exception, not the rule. 
 
So, how do you bring down the pH of your spray water if it is high? Commercial people use buffering agents but that may be difficult for homeowners to find. Food grade citric acid can help. If you have a pH of 8.0, add 2 ounces of this citric acid per 100 gallons of water (1 and 1/4 teaspoons per 10 gallons) to bring the pH down to about 5.5. (Ward Upham)

Some parts of Kansas will have at least a partial peach crop that wasn’t killed by late frosts. To take advantage of this good fortune certain things should be done as the fruit matures to ensure a good harvest.
 
Control insects and diseases: Though it is too late to control peach leaf curl (see http://www.hfrr.ksu.edu/doc3168.ashx ), it is possible to control scab and brown rot.  Insects of concern are plum curculio, oriental fruit moth, plant bugs, and stink bugs. Use Captan or Immunox to control the diseases, and malathion to control the insects. Spray every 10 to 14 days. Pay attention to the waiting period between the last spray and harvest. See the publication, “Fruit Pest Control for Home Gardens” at http://www.ksre.ksu.edu/bookstore/pubs/c592.pdf   for details including organic controls.
 
Thin peaches: Thin peaches to 1 every 6 to 8 inches to maximize fruit size and to decrease the load on the branches. As a general rule, we need about 40 leaves per peach for maximum quality. Peaches are borne in clusters, so calculate how many a branch can support by dividing the length of the branch in inches by 7. As long as there is an average of 7 inches of branch length per peach, it doesn’t matter whether the peaches are in clusters or not.
 
Water Trees as Needed:   The most critical time for adequate water is during the pit hardening stage which usually lasts between 2 to 4 weeks. Cut open a few peaches to determine when the pit starts to harden or become woody. Irregular watering during this period can lead to split peaches.
 
Prop up branches if needed: Prop up branches if the fruit load is so heavy the tree may break apart. Use boards with a “V” cut in one end to support the branch. Prune the branch back to a smaller side branch next spring (March). (Ward Upham)

A common disease of roses is blackspot, a fungus disease that can cause defoliation of susceptible plants. Look for dark, circular lesions with feathery edges on the top surface of the leaves and raised purple spots on young canes. Infected leaves will often yellow between spots and eventually drop.

 The infection usually starts on the lower leaves and works its way up the plant.  Blackspot is most severe under conditions of high relative humidity (>85%), warm temperatures (75 to 85 degrees F) and six or more hours of leaf wetness. Newly expanding leaves are most vulnerable to infection. The fungus can survive on fallen leaves or canes and is disseminated primarily by splashing water.
 
Cultural practices are the first line of defense.
 
1. Don't plant susceptible roses unless you are willing to use fungicide sprays. For a list of blackspot resistant varieties, go to:  http://www.ppdl.purdue.edu/ppdl/weeklypics/3-22-04.html
 
2. Keep irrigation water off the foliage. Drip irrigation works well with roses.
 
3. Plant roses in sun in areas with good air movement to limit the amount of time the foliage is wet.
 
4. Remove diseased leaves that have fallen and prune out infected rose canes to minimize inoculum.
 
If needed, protect foliage with a regular spray program (10- to 14-day schedule) of effective fungicides. Recommended fungicides include tebuconazole (Bayer Disease Control for Roses, Flowers and Shrubs), myclobutanil (Immunox, Immunox Plus), triticonazole (Ortho Rose & Flower Disease Control) and chlorothalonil (Broad Spectrum Fungicide, Garden Disease Control, others). (Ward Upham)

Leaves Turning Yellow or Red: In Kansas we often see chlorosis (yellowing) of plant leaves due to high pH soils making iron unavailable.  However, there can other causes that result in similar symptoms. For example, we have received so much rain in certain parts of the state recently that plants are unable to take up the nutrients needed to maintain a good green color. The cause of this condition is actually a lack of oxygen in the soil due to soil pore space being filled with water.
 
This lack of oxygen to the roots often results in a yellowing of foliage. In certain plants such as oaks and maples, however, it may also lead to a reddening of some of the newer leaves. Fortunately, color changes due to wet soils will be corrected as soils dry. Plants should regain their color when we return to more normal weather.
 
Trees Shedding Leaves: If trees shed leaves in a general shedding with all parts of the tree losing some leaves, then there is no cause for concern. A general shedding of the leaves is most often due to weather turning hot and dry. The tree drops leaves because the root system can no longer keep up. Dropping leaves helps balance the amount of water available from the root system and the amount needed by the leaves.
 
However, the same thing can happen if the soil is too wet. A lack of oxygen in the soil compromises the root system so it can no longer support all the leaves. Therefore, the tree drops some leaves to bring the tree roots and leaves back into balance. The tree will retain more than enough leaves to remain healthy. (Ward Upham)

The frequent, heavy rains in certain areas of the state have resulted in the appearance of mushrooms in home lawns and landscape beds.  Although mushrooms are often spectacular in size and color, most are relatively harmless to plant life. Some of these mushrooms are associated with arc-like or circular patterns in turfgrass called fairy rings. The ring pattern is caused by the outward growth of fungal mycelium. The mycelium forms a dense, mat-like structure in the soil that decomposes organic matter. This decomposition releases nitrate into the soil, which in turn stimulates the growth of the grass at the outer portion of the ring. This results in a dark green appearance of the grass at the margin of the ring.
 
Unfortunately, the thick fungal mat formed by the fungus interferes with water infiltration. The fungus also may release certain byproducts that are toxic to the turf. This can lead to dieback of the turf close to the ring. Fairy rings are difficult to control. You can sometimes eliminate the ring by digging to a depth of 6 to 12 inches and 12 inches wide on both sides of the ring, refilling the hole with non-infested soil. Or you can try to mask the symptoms by fertilizing the rest of the lawn so that it is as dark green as the ring. This often isn't a good idea because it tends to promote other turf problems. Commercial people can use certain fungicides to control fairy rings but these products are not available to homeowners. See http://www.ksre.ksu.edu/bookstore/pubs/EP155.pdf  for more info on these fungicides.
 
Some mushrooms in lawns are not associated with fairy rings. These may be mycorrhizal (symbiotic association with tree roots) or saprophytic (live on dead organic matter such as wood, etc.) in the soil. Because some of these mushrooms are beneficial, you don't really want to kill them. Besides, a fungicide spray to the mushroom itself does little good. Remember the mushroom is simply the fruiting structure of the organism. Most of the fungus is below ground and inaccessible to the chemical. If mushrooms are a nuisance, pick them and dispose of them as soon as they appear. Remove sources of large organic debris from the soil. Also, mushrooms tend to go away as soil dries. Patience may be the best control. Some of the mushrooms in the lawn are edible, but others are poisonous. Never eat mushrooms unless you are sure of their identity. (Ward Upham)

Aphids are small insects, about an eighth of an inch long. They are soft-bodied, pear-shaped and of many colors, such as green, black, gray, yellow or red. Some are winged during certain times of the year.
 
Aphids feed by sucking sap from buds, leaves, twigs and developing fruit. Most of that sap is passed through their body and ejected through two small “pipes” known as cornicles that project from the rear of their bodies. This ejected, sticky
material is called honeydew. This honeydew often becomes black with sooty mold fungus. Automobiles parked under trees with large aphid populations will often be spotted with honeydew. Though the finish will not be harmed by the honeydew, it is a hassle to clean off.
 
Aphids usually are controlled effectively by nature. Adverse weather conditions such as beating rains and low temperatures, as well as fungus diseases, insect predators and parasites, keep the aphids in check. Aphid enemies include lady beetles, syrphid fly larvae, aphis lions and small wasp parasites known as braconids.
 
Most insecticide applications destroy beneficial insects as well as pests and leave trees or shrubs unprotected if pest resurgence occurs. Because beneficial insects play an important role in natural aphid control, try washing aphids away with a forceful stream of water (if practical) before using insecticide sprays.
 
If control measures are warranted, use insecticidal soaps, horticultural oils, malathion, cyfluthrin or permethrin. Reapplication may be needed. Imidacloprid (Annual Tree and Shrub Insect Control, 12 Month Tree & Shrub Insect Control, Max Tree and Shrub Insect Control, Bonide Systemic Granules IC, Bayer Tree and Shrub Insect Control) is a systemic insecticide that can be used to prevent aphid populations from building but must by applied early to allow time for the pesticide to move to the new growth. This time period may vary from one week to three months depending on the size of the plant with very large trees taking the most time. (Ward Upham)

We had a report last week from the Wichita area that a number of ash trees have ash sawfly larvae feeding on the leaves.
 
These sawfly larvae are a light green color with a broad, whitish stripe on the top side.  In the middle of the whitish stripe there appears to be a darker green stripe that is actually the digestive tract of the insect.  Though sawfly larvae resemble caterpillars, they have at least six pairs of "stublike" prolegs behind the three pairs of true legs on their abdomen. (Caterpillars never have more than five pairs of prolegs.)
 
There are usually no detrimental effects to the health of the tree if nature is allowed to run its course. Even if all the leaves are eaten, it is early enough in the growing season for trees to put out a complete new set of leaves and still has enough time to make all the food reserves needed to survive the coming winter. However, if control is desired, a number of insecticides can be used for control including cyfluthrin (Bayer Lawn and Garden Multi-Insect Killer), malathion, esfenvalerate (Monterey Bug Buster II) and carbaryl (Sevin). An effective organic product is spinosad (Captain Jack’s Deadbug Brew; Fertilome Borer, Bagworm, Leafminer and Tent Caterpillar Spray; Monterey Garden Insect Spray). Horticultural oils and insecticidal soaps are also effective because of the soft skin of sawfly larvae. (Ward Upham)
 
Contributors:  Ward Upham, Extension Associate

If you have vegetables that are blooming but not setting fruit, you may have a problem with flower pollination. There are several possible reasons for this that usually vary by species. One condition that can affect several species at the same time is overfertilization. Too much nitrogen causes the plant to emphasize vegetative growth, often to the detriment of fruit production. Overfertilization can lead to a delay in flower production and a decrease in fruit set among the flowers produced.

Squash, cucumbers, watermelon, and muskmelon can have a couple of other problems. First, the early flowers on these plants are usually all male. The production of both male and female flowers becomes more balanced as time passes. You can easily tell the difference between the two because only the female flower has a tiny fruit behind the blossom. If you have both, have not over-fertilized, and still have a problem, make sure you have pollinators. Look for the presence of bees visiting the plants. If you don't see any, try hand-pollinating several flowers. Use a painter’s brush to transfer pollen from the anther of the male flower to the stigma of the female flower. If you get fruit on only those flowers you pollinated, you need more pollinators. Make sure you aren't killing them with overuse of insecticides.

Tomatoes are wind pollinated and therefore not dependent on pollinators. But they have another possible problem, which is temperature. Tomatoes normally won't set if the night temperature is below 50 due to sparse pollen production. They also won't set when nighttime temperatures are above 75 degrees F and daytime temperatures are above 95 degrees F with dry, hot winds. (Ward Upham)

Next year's strawberry crop will be affected by what you do to this year's strawberry bed. The sooner after harvest the patch is cleaned up, fertilized and irrigated, if possible, the better the chance of getting a good crop next year. One of the main goals in renovation is to provide a high level of sunlight to plant leaves so they can manufacture the food the plant needs. If leaves have disease spots, remove all the leaves in the bed. Removing these diseased leaves and weeds will cause new, non-diseased leaves to develop and remove competition from weedy plants. Hedge shears or even a mower can be used. Be sure the mower blade is high enough to avoid the strawberry crowns.

It is also important to reduce the number of strawberry plants so they do not compete for light, moisture and nutrients. If you have a small bed, you can hoe out or pull some plants so they are spaced about 4 to 6 inches apart. On large beds, adjust a rototiller so you can till between the rows, and cut each row back to about 10 inches wide.

The next step is to fertilize the plants with about 3/4 to 1 pound (3 to 4 cups) of a complete fertilizer such as 13-13-13 (nitrogen, phosphorus and potassium) or an equivalent on each 25 feet of row. If a soil test shows adequate levels of phosphorus and potassium, use 3/4 pound (1.5 cups) of a 16-0-0 (nitrate of soda) fertilizer per 25 feet of row instead. If nitrate of soda is unavailable, use the lawn fertilizer that contains about 30% nitrogen such as a 30-0-3, 28-0-3 or something similar. Make sure the lawn fertilizer does not contain a weed killer or preventer. These fertilizers should be used at the rate of 3/4 cup per 25 feet of row.

The next step is to irrigate to wash the fertilizer into the soil and provide moisture for the rapid growth of the strawberry plants. When the soil is dry, apply about 1 inch of water. A garden sprinkler can do a good job applying the water.

Controlling weeds and watering throughout the summer are important so plants are vigorous when fruit buds begin to develop in September and October. (Ward Upham)

Looking to add a bit of whimsy to your garden this year? I was recently on the hunt for a tree with interesting features that are a bit Dr. Seuss-like. You know, weeping habit, curvy trunks, pom-pom ball pruning…the whole nine yards.  I thought I’d share my finds with you in case you’ve got a curious child in your life that would really enjoy a fun plant.
I’m always interested in the actual plants, of course, but I think it’s interesting and worth noting how they grow the way they grow. Most interesting cultivars or varieties of ornamental plants are discovered by unusual growth called  “sports,” originate from a “witch’s broom,” involve unique traits on a seedling, hybrid or plant breeding resulting in polyploidism (bigger flowers, bigger fruit, but often brings sterility and cross fertilization incompatibility). However those unique traits are found, they are generally cloned (vegetative cuttings) and grafted onto more stable roots.

Of course there are always unique ways of pruning plants into topiaries as well, but let’s get into the plants.

If you’re looking all for a weeping tree, there are lots of choices. For starters, the redbud is a great plant for our region. You can’t go wrong with dark pink flowers in the spring and large, glossy, heart-shaped leaves in the summer.   Add a weeping feature and you’re in business. Popular weeping cultivars of redbud (Cercis canadensis)( are ‘Lavender Twist’ and ‘Ruby Falls.’ The latter has red/purple leaves in the summer.

Other deciduous weeping trees include Japanese Maple (Acer palmatum ‘Ryussen’), Mimosa (Albizia julibrissin ‘Pendula’), River Birch (Betula nigra ‘Summer Cascade’), European Hornbeam (Carpinus betulus ‘Pendula’), and Baldcypress (Taxodium distichum ‘Cascade Falls’ or ‘Falling Water’) just to name a few. Evergreen weeping plants can range from our native Eastern Redcedar (Juniperus virginiana ‘Pendula’) to Cedar of Lebanon (Cedrus  libani ‘Pendula’) and Atlas Cedar (Cedrus atlantica ‘Glauca Pendula’).

How about splendiferous plants with contorted stems and leaves? Corkscrew Willow (Salix matsudana ‘Tortuosa’) is a wonderful deciduous tree that fits the description. It’s just fascinating to look at all of the curly branches and stems. But this is a willow and it needs to be planted a good distance from your house and any water features. The roots of willow can be fairly invasive when looking for water sources.

In the shrub category, there is Harry Lauder’s Walkingstick (Corylus avellana ‘Contorta’). This is a fantastic plant for winter interest. In the summer it can be difficult to notice the uniquely contorted stems when the leaves cover the plant, but it’s a great specimen to bring some Dr. Seuss to leafless days. In the annuals category, a great plant for container gardens is Soft Rush (Juncus effusus). With cultivars like ‘Curly Wurly’, ‘Spiralis’ and ‘Unicorn’ you can be assured that someone will ask you about it.

How about pom pom type growth? Allium bulbs are great for this effect. They send up a single stalk with a round inflorescence at the top in spring and summer. There are many types with features ranging from size of the inflorescence, height of the stalk and color (purple to white). Smaller annual plants like Gomphrena have pom pom type inflorescences that are smaller, but more prolific. Great for containers or flower beds!

These plants are mostly what I’d call “specimen” plants and may be more difficult to find in the nursery than others. You may have to special order or mail order some of them, but they’re available. Hunting for plants for your Dr. Seuss plant collection or garden might just be the fun endeavor you’ve been looking for lately. (Cheryl Boyer)

Chiggers are mites, not insects. And like all mites, the adults have eight legs.  However, the larva only has six legs.

Though the bright red female adult is tiny (about 1/20th of an inch) the larva is much smaller (about 1/150th of an inch). Only the larvae are parasitic and attack animals. The larva injects digestive juices into the skin, which causes a rapid swelling. In the center of the swelling is a "feeding tube" from which the chigger sucks out liquefied skin cells. Feeding usually continues for 2 to 4 days.

Protection from chiggers uses two approaches. The use of a repellent can discourage chiggers from attacking. The most effective repellents are Deet and permethrin. Both are applied to clothing. The second approach seeks to reduce chigger populations. Keeping the lawn mowed regularly can help, but large populations may require the use of an acaricide. Effective products include bifenthrin (Talstar, Hi-Yield Bug Blaster II, Hi-Yield Bug Blaster Bifenthrin, and Ortho Lawn Insect Killer Granules), cyfluthrin (Tempo 20, Bayer Vegetable & Garden Insect Spray) and carbaryl (Sevin). For more information, see the K- State Research and Extension publication titled, “Chiggers” at: http://www.ksre.ksu.edu/bookstore/pubs/MF2107.PDF     (Ward Upham)

Several new publications have been released recently that should be helpful to gardeners.

Harlequin Bug (MF3135) - A destructive pest of vegetable crops, especially the cole crops such as broccoli, cabbage and cauliflower.

Japanese Beetle (MF3151) -   Though this insect became established in Kansas in 1992, it remained confined to certain areas of the state for a number of years.  However, populations have been increasing and new areas are becoming infested.   Japanese beetle has a very wide host range (reportedly 300 to 400 plant species) including many vegetables, fruits and ornamentals.

Spotted Wing Drosophila (MF3158) - First detected in Kansas in 2013, this pest of fruit can attack a wide variety of small fruit including blackberries, blueberries, boysenberries, raspberries, strawberries, and grapes. Raspberries appear to be more susceptible than blackberries, blueberries, and strawberries.  Tree fruit such as apples, cherries, figs, nectarines, peaches, persimmons, and plums can also be attacked.

Tree and Shrub Problems in Kansas: Diseases, Insects, and Environmental Stresses (MF3132) - We have mentioned this one before but wanted to highlight it again as it is a very valuable resource.  This is a 92-page publication with 116 color images to help with identification. (Ward Upham)

These finger-shaped mushrooms live up to their name.  As they mature, they become extremely foul smelling.  The odor is reminiscent of rotting meat or, in some cases, of what a dog leaves behind after it has done its “business.”

Stinkhorn mushrooms live on dead organic matter such as is found in mulched areas (especially bark mulch), fields or in yards.  The finger-like fruiting body arises from a sac-like structure at the base.  A slimy spore mass eventually develops at the tip of the stalk.  It is the spore mass that causes the odor.  This spore mass also attracts flies which help spread the spores to new areas.

The question always comes up on how to prevent or control these mushrooms.  Since the main part of the fungus, the mycelium, is underground there isn’t anything you can do but remove the mushrooms as they appear.  Remember the mushroom is the fruiting body of the mushroom and it is the mycelium that must be controlled to prevent the mushrooms.  (Ward Upham)

Contributors: Cheryl Boyer, Nursery Crops Specialist; Ward Upham, Extension Associate

This time of year, two common leaf-spot diseases appear on tomato plants. Septoria leaf spot and early blight are both characterized by brown spots on the leaves.

Septoria leaf spot usually appears earlier in the season than early blight and produces small dark spots. Spots made by early blight are much larger and often have a distorted “target” pattern of concentric circles. Heavily infected leaves eventually turn yellow and drop. Older leaves are more susceptible than younger ones, so these diseases often start at the bottom of the plant and work up.

Mulching, caging, or staking keeps plants off the ground, making them less vulnerable. Better air circulation allows foliage to dry quicker than in plants allowed to sprawl. Mulching also helps prevent water from splashing and carrying disease spores to the plant.  

In situations where these diseases have been a problem in the past, rotation is a good strategy. It is too late for that now, but keep it in mind for next year. Actually, rotation is a good idea even if you have not had problems in the past. But many gardens are too small to make it practical. If you have room, rotate the location of the tomatoes each year to an area that has not had tomatoes or related crops (peppers, potatoes, eggplant) for several years.

If rotation is not feasible, fungicides are often helpful. Be sure to cover both upper and lower leaf surfaces, and reapply fungicide if rainfall removes it. Plants usually become susceptible when the tomato fruit is about the size of a walnut. Chlorothalonil is a good choice for fruiting plants because it has a 0-day waiting period, meaning that fruit can be harvested once the spray is dry.  Chlorothalonil can be found in numerous products including Fertilome Broad-Spectrum Landscape and Garden Fungicide, Ortho Garden Disease Control, GardenTech Daconil and others. Be sure to start protecting plants when the disease is first seen. It is virtually impossible to stop it on heavily infected plants.

If chlorothalonil doesn’t seem to be effective, try mancozeb (Bonide Mancozeb Flowable). Note that there is a five-day waiting period between application and when the fruit can be harvested. You may wish to pick some tomatoes green just before you spray if you use Mancozeb as they will ripen inside. (Ward Upham)

This is the time of year that onions grow and develop rapidly. Regular watering (if needed) and a light fertilization are helpful to maximize growth. Onions develop so that as much as 2/3 of the bulb remains out of the soil. This is normal and there is no need to cover the bulb with soil.

A gardener can tell when onions are nearing harvest time by some of the tops falling over. You may wish to break over the tops that haven’t fallen to encourage drying of the neck. Allow a few days to pass and then dig the onions to insure they don’t sunburn. Temporarily store them in a dry, well-ventilated area for a week or two before cutting the tops to insure the necks are completely dry. Remove the foliage (or braid the leaves) and store in a cool, dry location. (Ward Upham)

Rose rosette is a serious problem in Kansas on wild roses (Rosa multiflora) in pastures and hedges. It has also occasionally been found in domestic rose plantings.

Infection is thought to start with rapid elongation of a new shoot. The rapid shoot growth may continue for several weeks to a length of two to three feet. Following shoot elongation, a witches' broom or clustering of small branches occurs. The stems develop excessive thorniness and produce small, deformed leaves with a reddish-purple pigmentation. Stems and petioles of Rosa multiflora plants may have reddish blotches or streaks. Rose plants infected with the rose rosette virus die rapidly, usually within one to two years.    

Rose rosette is caused by an Emaravirus species.  Transmission of the disease has been shown experimentally through grafting and is also thought to be spread by mites. Though KnockOut roses are resistant to many diseases, they are susceptible to this one.

There is no effective control measure for infected plants. In garden settings, infected plants should be removed and destroyed, including roots. Any roots that remain after plant removal may produce infected shoots which can harbor the disease.

If possible, eliminate all multiflora rose plants from the vicinity as they are extremely susceptible and will act as a carrier. Multiflora rose is the wild rose often seen growing in ditches and pastures. Since the disease can be transmitted by pruning shears, disinfect the shears when moving from one plant to another by using rubbing alcohol or a disinfectant such as Lysol. (Ward Upham)

Every year we see damage caused by exposure to herbicides. Symptoms vary with herbicide applied, plants exposed, concentration of product and environmental factors. Here is a list of the types of damage commonly seen.

Broadleaf herbicide drift. A number of herbicides used on farms and on home lawns are essentially plant growth hormones. These include 2,4-D, triclopyr, and dicamba and are commonly used to control broadleaf weeds in lawns, pastures, or grassy crops. These products may become a gas (volatilize) at high temperatures, causing them to drift and damage nontarget plants such as trees and shrubs. Symptoms may include twisting and distortion of plant foliage, leaf yellowing, and, in severe cases, branch dieback. One of the trademark signs of this damage is the curly-Q twisting of leaf petioles or stems. Though tomatoes, redbud trees, and grapes are sensitive to these herbicides, a number of species will show some damage if drift has occurred. If you see twisting on more than one species, chances are that herbicide drift has occurred. Often, plants recover from drift due to volatilization.

Damage to vegetable gardens. Though drift is the most common cause of herbicide damage on vegetables, other potential problems exist as well. Cattle fed prairie hay from pasture treated with picloram (Tordon) can have manure tainted with the herbicide. If this manure is used on a vegetable garden, plants may sicken and die. Also, lawn clippings treated with quinclorac (a crabgrass killer) and used as mulch can have the same effect. Both products can remain active for up to 24 months.

Damage from stump or sprout treatments. Tree stumps often are treated to prevent resprouting. Two commonly used products are picloram (Tordon) and triclopyr (Remedy, Stump Killer, Brush-B-Gon, etc.). Be careful when applying these herbicides to prevent contamination of the soil. Nearby trees may be damaged if they pick up enough herbicide. Foresters warn that picloram also may leach from roots of a treated tree into the soil and be absorbed by roots of another tree species. This does not occur with triclopyr. Be very careful about using these products near valuable trees and shrubs.

Sprouts are often treated to keep them from growing where they interfere with the aesthetics of a lawn or other landscaped area. Never use a herbicide to treat sprouts coming from a root system of a tree you want to keep. A number of tree species including honey locust, black locust, hackberry, western soapberry, persimmon, and occasionally, maples may send up sprouts from their roots.

Treating these sprouts will effectively treat the tree to which they are attached. This may ultimately kill the tree. Also remember that trees of the same species growing next to one another may share a root system as a result of root grafting. Treating one tree in the group is like treating all of the trees.

If treating volunteer sprouts, use a product such as Monterey Sucker-Stopper. It will not harm the plant to which the sprouts are attached.


Liquid Weed Edgers. Herbicides are often used along fences, on sidewalks or gravel drives to prevent plant growth. Some of these, including glyphosate (Roundup) and glufosinate (Finale) rarely causes damage unless sprayed directly on the foliage of a shrub or tree. Other liquid weed edger products are soil sterilants and have a long residual (months to years) in soil and are highly toxic to trees and shrubs. Symptoms may include yellowing, marginal leaf scorching, branch dieback and tree mortality. Once the tree takes up these products through their roots, they suffer permanent damage. Never use these soil sterilants in areas where tree roots may be exposed.  Remember that tree roots extend well beyond the drip line. It is almost impossible to use liquid weed edgers in the landscape without coming in contact with tree roots. Also remember that some of these products, such as prometon, will move with water until they become affixed to the soil. (Ward Upham)

Squash bugs are the grey, shield-shaped bugs that feed on squash and pumpkin plants. If you have had problems with these insects in the past, you know that they are almost impossible to control when mature. This is because the squash bugs have a hard body that an insecticide has difficulty penetrating. Thus, spraying when the insects are small is important. We are now seeing the nymphs of the first generation. These nymphs will eventually become adults, which will lay eggs that will become the second generation. The second generation is often huge and devastating. Therefore, it is important to control as many squash bugs now as possible.

Because squash bugs feed by sucking juice from the plant, only insecticides that directly contact the insect will work. General use insecticides such as permethrin (Bug-B-Gon Multi-Purpose Garden Dust, Green Thumb Multipurpose Garden and Pet Dust, Bug-No-More Yard and Garden Insect Spray, Eight Vegetable, Fruit and Flower Concentrate, Garden, Pet and Livestock Insect Control, Lawn & Garden Insect Killer), malathion, and methoxychlor provide control if a direct application is made to young, soft-bodied squash bugs. This means that you MUST spray or dust the underside of the leaves because this is where the insects live. (Ward Upham)

Daytime/midday butterfly flurries along trails invariability are attributed to hackberry caterpillar butterflies. Outbreaks of hackberry butterflies are sporadic and unpredictable. While hackberry butterflies are present every year and often go unnoticed, “outbreaks” may cause concern.

Exact reasons to explain outbreaks are unknown. An often-cited reason to explain them is the  mildness or severity of the previous winter. This breaks down, however, if one looks at a relatively limited geographical area experiencing a spate of hackberry butterflies, against other areas which experienced the same winter conditions ---- which begs the question, “Why here and not there?”

The definitive work done by C. V. Riley in Missouri )1874( documented that hackberry butterflies produced 2 generations per year, with the larvae emerging from the eggs of second generation moths being the overwintering form. Based on this, there would be little reason not to expect the same 2 generation scenario in Kansas.  So what is the commotion about regarding hackberry caterpillar butterflies? It is the butterfly themselves, as well as the impact of larval activities.

The presence of the larvae precedes that of the butterflies. The head of the larva has an interesting look: a black horned appearance.

In the absence of people, hackberry caterpillars go about their business without causing concern. However when people decide to “invade” the domain of hackberry caterpillars, a couple of situations occur. First, if picnicking beneath hackberry trees in which caterpillars are feeding, the rain-of-fecal pellets can be unappetizing.

Second, after caterpillars have completed their feeding up in the canopy of hackberry trees, they descend to the ground in search of a site in which they will pupate. This stream of caterpillars (again in the presence of people) may be disconcerting.

Tremendous numbers of larvae translate into eventual tremendous numbers of butterflies. Thus, the “nuisance factor” continues upon completion of pupation and the emergence of the “new” butterflies. (Bob Bauernfeind)

This is a new pest for me, but I have had two calls on elm flea weevil causing damage to Siberian elm in the last week.  One was from northern Kansas (Mitchell County) and the other further south in the Wichita area. Though this weevil does feed on other elms including American and Chinese elms, Siberian elm is preferred.

The adult of this insect is a very small (1/8 inch) brown weevil with dark spots on the back. It sports a short, curved snout and has the ability to hop.

Eggs from overwintering adults hatch on newly formed leaves.  The larva produces a serpentine pattern in the leaf that terminates on a leaf edge.  Adults have emerged now and are feeding on the leaves.  Adult feeding damage produces a shothole pattern in the leaves.  Heavily fed upon leaves appear lacy.  There is one generation per year and so when the adults disappear, there should be no further damage this year.

I have not seen any control strategies for this insect.  Trees typically recover from spring defoliations.  (Ward Upham)

The frequent, heavy rains in certain areas of the state have resulted in the appearance of mushrooms in home lawns and landscape beds.  Although mushrooms are often spectacular in size and color, most are relatively harmless to plant life. Some of these mushrooms are associated with arc-like or circular patterns in turfgrass called fairy rings. The ring pattern is caused by the outward growth of fungal mycelium. The mycelium forms a dense, mat-like structure in the soil that decomposes organic matter. This decomposition releases nitrate into the soil, which in turn stimulates the growth of the grass at the outer portion of the ring. This results in a dark green appearance of the grass at the margin of the ring.

Unfortunately, the thick fungal mat formed by the fairy ring fungus interferes with water infiltration. The fungus also may release certain byproducts that are toxic to the turf. This can lead to dieback of the turf close to the ring. Fairy rings are difficult to control. You can sometimes eliminate the ring by digging to a depth of 6 to 12 inches and 12 inches wide on both sides of the ring, refilling the hole with non-infested soil. Or you can try to mask the symptoms by fertilizing the rest of the lawn so that it is as dark green as the ring. This often isn't a good idea because it tends to promote other turf problems. Commercial people can use certain fungicides to control fairy rings but these products are not available to homeowners. See http://www.ksre.ksu.edu/bookstore/pubs/EP155.pdf  for more info on these fungicides.        

Some mushrooms in lawns are not associated with fairy rings. These may be mycorrhizal (symbiotic association with tree roots) or saprophytic (live on dead organic matter such as wood, etc.) in the soil. Because some of these mushrooms are beneficial, you don't really want to kill them. Besides, a fungicide spray to the mushroom itself does little good. Remember the mushroom is simply the fruiting structure of the organism. Most of the fungus is below ground and inaccessible to the chemical. If mushrooms are a nuisance, pick them and dispose of them as soon as they appear. Also, remove sources of large organic debris from the soil. Also, mushrooms tend to go away as soil dries. Patience may be the best control. Some of the mushrooms in the lawn are edible, but others are poisonous. Never eat mushrooms unless you are sure of their identity. (Ward Upham)   

Contributors: Bob Bauernfeind, Entomologist; Ward Upham, Extension Associate