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How to Plant a Tree

9/18/2017

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Planting Trees in the Fall

9/18/2017

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The fall season can be an excellent time to plant trees. During the spring, soils are cold and may be so wet that low oxygen levels inhibit root growth. The warm and moist soils normally associated with fall encourage root growth. Fall root growth means the tree becomes established months before a spring-planted tree and is better able to withstand summer stresses. The best time to plant trees in the fall is early September to late October.  This is early enough that roots can become established before the ground freezes.  Unfortunately, certain trees do not produce significant root growth during the fall and are better planted in the spring. These include beech, birch, redbud, magnolia, tulip poplar, willow oak, scarlet oak, black oak, willows, and dogwood. 
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Fall-planted trees require some special care. Remember, that roots are actively growing even though the top is dormant. Make sure the soil stays moist but not soggy. This may require watering not only in the fall but also during the winter months if we experience warm spells that dry the soil. Mulch also is helpful because it minimizes moisture loss and slows the cooling of the soil so root growth continues as long as possible. (Ward Upham)

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Miscellaneous: New Publication on Planting Trees

5/30/2017

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Cathie Lavis, our Landscape Specialist has authored a new publication on planting trees. This is a two-page publication with the first page covering the proper planting of a ball-in-burlap tree, and the second page covering container-grown trees. If you want a newly planted tree to survive and thrive, proper planting is vital.  You can find the publication at: https://www.bookstore.ksre.k-state.edu/pubs/MF3313.pdf  (Ward Upham)

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Ornamentals: Ten Rules for Planting Trees

3/14/2017

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Before you begin spring landscaping, here are some tips on planting trees.
 
1. Select the right tree for the site. To avoid serious problems, choose trees that are adapted to your location. Consider whether the tree produces nuisance fruit or if there are disease-resistant varieties available. For example, there are a number of crabapple varieties that are resistant to apple scab and rust diseases. Also consider the mature size of a tree to be sure you have enough room. See http://hnr.k-state.edu/extension/info-center/recommended-plants/index.html  or ask a local nurseryman for suggestions for trees adapted to your area.
 
2. Keep the tree well watered and in a shady location until planting. When moving the tree, lift it by the root ball or pot and not by the trunk.
 
3. Before planting, remove all wires, labels, cords or anything else tied to the plant. If left on, they may eventually girdle the branch to which they are attached. The root flare (point where trunk and roots meet) should be visible. If it isn't, remove enough soil or media so that it is.
 
4. Dig a proper hole. Make the hole deep enough so that the tree sits slightly above nursery level. Plant the tree on solid ground, not fill dirt. In other words, don't dig the hole too deep and then add soil back to the hole before placing the tree.
 
The width of the planting hole is very important. It should be three times the width of the root ball. Loosening the soil outside the hole so it is five times the diameter of the root ball will allow the tree to spread its roots faster.
 
5. Remove all containers from the root ball. Cut away plastic and peat pots; roll burlap and wire baskets back into the hole, cutting as much of the excess away as possible. If you can remove the wire basket without disturbing the root ball, do it. If roots have been circling around in the container, cut them and spread them out so they do not continue growing so that they circle inside the hole and become girdling roots later in the life of the tree.
 
6. Backfill the hole with the same soil that was removed. Amendments such as peat moss likely do more harm than good. Make sure the soil that goes back is loosened - no clods or clumps. Add water as you fill to ensure good root to soil contact and prevent air pockets. There is no need to fertilize at planting. Note: Adding organic matter to larger area than just the planting hole can be beneficial, but it must be mixed in thoroughly with the existing soil. However, adding amendments to just the planting hole in heavy soil creates a “pot” effect that can fill with water and drown your new tree.
 
7. Don't cut back the branches of a tree after planting except those that are rubbing or damaged. The leaf buds release a hormone that encourages root growth. If the tree is cut back, the reduced number of leaf buds results in less hormone released and therefore fewer roots being formed.
 
8. Water the tree thoroughly and then once a week for the first season if there is insufficient rainfall.
 
9. Mulch around the tree. Mulch should be 2 to 4 inches deep and cover an area two the three times the diameter of the root ball. Mulching reduces competition from other plants, conserves moisture and keeps soil temperature closer to what the plants' roots prefer.
 
10. Stake only when necessary. Trees will establish more quickly and grow faster if they are not staked. However, larger trees or those in windy locations may need to be staked the first year. Movement is necessary for the trunk to become strong. Staking should be designed to limit movement of the root ball rather than immobilize the trunk. (Ward Upham)

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Horticulture Newsletter 2017, No.3

1/17/2017

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Video of the Week:
Flower Bed Design

Trees:
Pruning Storm Damaged Trees

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​Winter storms may cause serious tree damage.  Often you will have to decide whether a tree can be saved or not. Here is a checklist on care of a storm-damaged landscape.

1. Be careful: Slippery ice and chainsaws don’t mix.  Wait until all ice has melted before beginning work.  

Check for downed power lines or hanging branches. Don't venture under the tree until it is safe. If large limbs are hanging precariously, a certified arborist has the tools, training and knowledge to do the work safely.

2. Cleanup: Remove debris so you don't trip over it.

3. Decide whether it is feasible to save a tree. If the bark has been split so the cambium is exposed or the main trunk split, the tree probably will not survive and should be removed. If there are so many broken limbs that the tree’s form is destroyed, replacement is the best option.

Topping, where all the main branches are cut and there are only stubs left, is not a recommended pruning procedure. Though new branches will normally arise from the stubs, they are not as firmly attached as the original branches and more likely to break in subsequent storms. Also, the tree must use a lot of energy to develop new branches, leaving less to fight off diseases and insect attacks. Often, the topped tree's life is shortened.

4. Prune broken branches to the next larger branch or to the trunk. If cutting back to the trunk, do not cut flush with the trunk but rather at the collar area between the branch and the trunk. Cutting flush with the trunk leaves a much larger wound than cutting at the collar and takes longer to heal. Middle-aged or younger vigorous trees can have up to one-third of the crown removed and still make a surprisingly swift comeback.

5. Take large limbs off in stages. If you try to take off a large limb in one cut, it will often break before the cut is finished and strip bark from the tree. Instead, first make a cut about 15 inches from the trunk. Start from the bottom and cut one-third of the way up through the limb. Make the second cut from the top down but start 2 inches further away from the trunk than the first. The branch will break away as you make the second cut. The third cut, made at the collar area, removes the stub that is left.

Note: Pruning can be dangerous. Consider hiring a trained, certified arborist to do major work.  Also, a good arborist knows how to prune trees so that storm breakage is less likely to occur. Preventing damage is better than trying to fix it once it has happened. The Arbor Day Foundation maintains an excellent Web site that contains detailed information. The URL is: http://www.arborday.org/media/stormindex.cfm     (Ward Upham)

Dutch Elm Disease Resistant American Elms

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Our John C. Pair Horticultural Center near Wichita established a National Elm Trial in 2007 with 18 cultivars. All of these are Dutch Elm Disease (DED) Resistant with 4 being true American elms. The cultivar ‘Jefferson’ would have been a fifth true American elm but proved to be the same cultivar as ‘Princeton’. The remainder are either hybrids or other elm species. The four true American elms are ‘Valley Forge’, ‘Princeton’, ‘New Harmony’ and ‘Lewis and Clark’ (Prairie Expedition). All have shown excellent tolerance to DED. Characteristics listed below are primarily from our study at the John C. Pair Horticultural Center but storm breakage is from the University of Minnesota. See http://www.extension.umn.edu/environment/agroforestry/elm-trees.html  for the Minnesota study.

‘Valley Forge’
Survival: 100%
Crown Shape: Vase
Lacebug damage to foliage: Minimal
European elm flea weevil damage: Minimal
Storm Breakage: Fair
Comments: Strong grower, broad spreading

‘Princeton’
Survival: 100%
Crown Shape: Vase
Lacebug damage to foliage: Minimal
European elm flea weevil damage: Minimal
Storm Breakage: Fair
Comments: Impressive grower, upright habit, attractive tree

‘New Harmony’
Survival: 100%
Crown Shape: Vase and round
Lacebug damage to foliage: Significant
European elm flea weevil damage: Minimal
Storm Breakage: Not in Minnesota study
Comments: Narrow, upright habit with strong, central axis

‘Lewis and Clark’ (Prairie Expedition)
Survival: 80%
Crown Shape: Broad oval
Lacebug damage to foliage: Minimal
European elm flea weevil damage: Minimal
Storm Breakage: Good
Comments: Strong grower with broad spreading habit, some wetwood.

Storm damage can be minimized by pruning when the tree is young. Maintain a central leader but prune out all lower branches as the tree grows and branches increase in diameter so that there is room to work under the tree. Also prune out branches attached with a narrow angle as these are most likely to give way in ice or wind storms. For photos and more information from our John C. Pair Horticultural Center, see
http://webdoc.agsci.colostate.edu/bspm/Kansas%20Elm%20Trial%20Nov%2012%202014.pdf 
(Ward Upham)

Start Trees Off Right

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​Research from K-State’s John C. Pair Horticultural Center has quantified the effect of controlling grasses around newly planted trees. Jason Griffin, William Reid, and Dale Bremer conducted a study to investigate the inhibition of growth of transplanted, seedling trees when lawn grasses were allowed to grow up to the trunk. There were five treatments, including three with different species of grass:

    1. Bare soil maintained with herbicides.
    2. Area under tree mulched 3 inches deep.
    3. Tall fescue allowed to grow under tree.
    4. Bermudagrass allowed to grow under tree.
    5. Kentucky bluegrass allowed to grow under tree.

All treatments were applied to Eastern redbud seedlings as well as to pecan seedlings. All trees were fertilized according to recommendations and watered during the growing season with up to 1 inch of water if rainfall was deficient. At the end of two years, trees were measured and harvested. Data was taken on caliper (diameter) 6 inches above the ground, weight of aboveground portions of the tree, leaf area, and leaf weight. There were no differences in any measure between the mulched treatment and the bare soil treatment for either tree species. All measures showed significant growth increases if lawn grasses were controlled around the tree.

Results include the following:

1. Caliper: Caliper measures 6 inches above the soil surface were twice as large for plots without grass than for those with either fescue or bluegrass, but only 50% larger when compared to the bermudagrass plots.

2. Top growth weight: Redbuds showed a 300% weight advantage for plots with grasses controlled than those without. Pecans showed a significant 200% increase.

3. Leaf area and leaf weight: Leaf areas were 200% larger in plots without grass competition and leaf weight showed a 300% increase.

The obvious conclusion from this study is that grasses must be controlled under a newly transplanted tree to get the best possible growth. Though there were no differences in growth whether mulch was used or not, you may still wish to mulch for aesthetic reasons or to help control weed growth. How far from the trunk should the grasses be controlled? Try a minimum of 3 feet. (Ward Upham)

Landscaping:
Now is a Good Time to Design Your Landscape

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The dark, cold days of winter are a good time to dream and plan for the upcoming growing season. Have you always wanted to landscape your home but didn’t know where to start? We offer a number of publications available to help you accomplish your dream. This collection includes everything from general landscaping publications such as “Residential Landscape Design,” to specific works such as “Naturalistic Landscaping” and “Low-Maintenance Landscaping.” 

You can download printed publications for landscaping free of charge from http://hnr.k-state.edu/extension/publications/landscaping.html. Information on plants recommended for Kansas can be found at http://hnr.k-state.edu/extension/info-center/recommended-plants/index.html 

You may also request printed copies from your local K-State Research and Extension office. There may be a small charge for printed copies of larger publications. 

If you need to know how to contact your local extension office, go to http://www.ksre.ksu.edu/Map.aspx and mouse over your county. (Ward Upham)

Fruit:
Fruit Trees and Frost

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If you are considering purchasing fruit trees this spring, there are certain factors that should be considered for some of our fruit tree species.  Spring in Kansas is often unsettled with apricot and peach tree flowers being very vulnerable to late frosts that can kill fruit buds. Of course, the tree itself will be fine but there will be no to little fruit for that year. Other species of trees can also be affected but apricots and peaches are by far the most sensitive.  Also, the closer a tree is to full bloom, the more sensitive it becomes to frost.

Apricots are more likely to have frost kill flowers than peaches because they bloom a bit earlier. Though there are late-blooming apricot varieties, the differences between full bloom on early and late-blooming varieties appears to be slight. Research at Virginia Tech in the 90's showed a maximum of a 4-day difference between early and late varieties. However, in some years that may be all that is needed. The trees in the study that were considered late blooming included Hungarian Rose, Tilton and Harlayne. Harglow was not included in the study but is also considered late-blooming. See https://pubs.ext.vt.edu/422/422-761/422-761.html  for more info.

Peaches are next on the list for being likely to be caught by a late frost. With peaches, two characteristics become important when considering whether they will be damaged. Like apricots, bloom time is very important but fruit bud hardiness should also be considered. In this case, fruit bud hardiness refers to hardiness to late frosts rather than the ability to survive extreme low temperatures during the winter. Late bloomers included ‘China Pearl’, ‘Encore’, ‘Intrepid’, and ‘Risingstar.’ See http://aces.nmsu.edu/pubs/research/horticulture/RR782.pdf. The ‘Intrepid’ cultivar also has shown excellent cold hardiness when in flower. See http://www.google.com/patents/USPP12357 

So, are there other considerations when looking at possible frost damage? Location can be very important. Planting on a hill which allows cold air to drain to lower elevations can help.  Also, a location in town will be more likely to have a warmer micro-climate than an exposed location. Some gardeners will add a heat source under a tree during cold nights if they are close to a building. Heat lamps and charcoal briquettes are sometimes used but safety should be the first consideration. (Ward Upham)

Pawpaw Trees: A Native Fruit

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Even though pawpaw is native to eastern Kansas, many people in the state have never eaten one. Fruits resemble fat bananas and are generally up to 6 inches long and as much as 3 inches wide. The taste is unique and is difficult to describe but is often said to resemble bananas or pineapple and has a texture somewhat like custard. They are rarely grown commercially because they are difficult to ship and do not store well. Ripe fruit will only hold 2 to 3 days at room temperature and up to a week under refrigeration.

Pawpaw prefers a well-drained, moderately acid (pH 5.5 to 7.0), moist soil and high organic matter content. Organic mulch is also recommended. Irrigation will be helpful to necessary depending on what part of Kansas they are grown.

In the wild, the pawpaw is an understory tree and may do better with partial shade, especially during the first 2 to 3 years. Protection from high winds is also advisable due to the large leaves. The pawpaw is a small tree that may reach 20 feet high but is less broad. Trees require cross-pollination and so at least 2 and preferably 3 different varieties should be grown. These trees are pollinated by insects other than bees such as beetles and flies and must be planted close together. Trees should be no further than 30 feet apart in order to insure good pollination. 

The soil for planting should be prepared in advance of receiving the trees. Amend the soil with organic matter in the area where the trees will be planted. Do not amend just the soil from the planting hole especially if the soil is heavy and has high clay content. If you do, you have essentially made a pot that will hold water and may drown the tree. Rather add organic matter to the area in which the tree will be planted before digging the planting hole; at least a 10- by 10-foot square. You may want to treat the entire area where your trees will be planted. Add 2 inches of organic matter to the surface of the soil and then till in. 

The planting hole should be the same depth as the root system but 2 to 3 times as wide. Pawpaws have fleshy roots and are better planted in the spring (April) rather than fall unless container grown. Container-grown plants can be planted virtually anytime.

Keep newly planted trees well watered. The soil should be moist but not waterlogged. Keep the planting area completely free of weeds or any other type of vegetation within 3 feet of the trees. Mulching is recommended.

There has been a significant amount of work done on pawpaw by Kentucky State University. You can reach their pawpaw site at http://www.pawpaw.kysu.edu/. Information on growing pawpaws is available from Peterson Pawpaws at http://www.petersonpawpaws.com. Neil Peterson’s pawpaws are the result of over 25 years of research and have been widely tested. Though Neil no longer sells his varieties directly, he does list a number of nurseries that carry them.

The Kansas Forest Service (www.kansasforests.org) has seedling trees available for sale though I would recommend getting named varieties instead if you wish to plant only a few trees. The fruit from named varieties will be of a higher quality than that from a seedling tree.  Named variety pawpaws are available from Stark Brothers (www.starkbros.com) and one from Raintree Nursery (www.raintreenursery.com).

The University of Missouri has a couple of different pawpaw cultivar trials. You can find results from one of these trials at http://www.centerforagroforestry.org/pubs/pawpaws.pdf  (Ward Upham)

Miscellaneous:
Bird Feeding

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Severe winter weather is not only hard on people but can be a life and death struggle for birds. Though birds also require water and shelter, food is often the resource most lacking during cold weather. Many different bird food mixes are available because various species often prefer different grains. However, there is one seed that has more universal appeal than any other: black oil sunflower. If you are new to the bird-feeding game, make sure there is a high percentage of this seed in your mix. White proso millet is second in popularity and is the favorite of dark-eyed juncos and other sparrows as well as the red-winged blackbird. 

As you become more interested in bird feeding, you may want to use more than one feeder to attract specific species of birds. Following is a list of bird species with the grains they prefer.
    - Cardinal, evening grosbeak and most finch species – sunflower seeds, all types.
    - Rufous-sided towhee – white proso millet.
    - Dark-eyed junco – white and red proso millet, canary seed, fine cracked corn.
    - Many sparrow species – white and red proso millet.
    - Bluejay – peanut kernels and sunflower seeds of all types.
    - Chickadee and tufted titmouse – peanut kernels, oil (black) and black-striped sunflower seeds.
    - Red-breasted nuthatch – oil (black) and black-striped sunflower seeds.
    - Brown thrasher – hulled and black-striped sunflower seeds.
    - Red-winged blackbird – white and red proso millet plus German (golden) millet
    - Mourning dove – oil (black) sunflower seeds, white and red proso plus German (golden) millet.

Extended cold periods can also make water unavailable. A heated birdbath can be a tremendous draw for birds during times when all other water is frozen. Energy use is usually less than what most people expect IF the heater has a built-in thermostat. If you would like more information, Chuck Otte, Agriculture Extension Agent for Geary County has a series of backyard birding guides at http://gearycountyextension.com/NRMW.htm  (Ward Upham)

Contributors: Ward Upham, Extension Associate

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Horticulture Newsletter 2016, No. 38

9/20/2016

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Video of the Week:
Protecting Fruit Trees from Deer

Flowers:
Time to Plant Spring-flowering Bulbs

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Late September through October is an excellent time to plant spring-flowering bulbs such as crocus, tulips, and daffodils. These plants need to develop roots in the fall and must meet a chilling requirement over the winter in order to bloom in the spring.
 
Choose a planting site that has full sun to partial shade. The ideal soil would be a sandy loam, but even poor soils can be used if organic material such as peat moss, compost, or aged bark is mixed in. For example, a heavy clay can be amended by mixing in one-third to one-half organic material. Soil pH should be between 6.0 and 7.0.
 
Bulbs need good aeration as well as good drainage for proper development. It is best if the bulbs are given 12 inches of prepared soil. If one-third organic material were added, this would require mixing 4 inches of organic material with 8 inches of soil. Incorporate about 3 pounds of a complete fertilizer such as a 5-10-5 per 100 square feet during preparation or fertilize according to soil test.
 
Planting depths vary depending on the size of the bulbs. For example, tulips and hyacinths are set about 6 inches deep, and daffodils are put 6 to 8 inches deep. Smaller bulbs are planted shallower. As a rule of thumb, bulbs are planted two to three times as deep as their width. Planting depth is the distance from the bottom of the bulb to the top of the soil. Large bulbs are normally spaced 4 to 6 inches apart, and small bulbs about 1 to 2 inches. Planting in clumps or irregular masses produces a better display than planting singly.
 
After placing the bulbs at the proper depth, replace half the soil and add water. This will settle the soil around the bulbs and provide good bulb/soil contact. Add the remaining soil and water again. Although there will be no top growth in the fall, the roots are developing, so soil needs to be kept moist but not soggy. Mulch can be added after the soil has frozen to prevent small bulbs from being heaved out of the soil by alternate freezing and thawing. (Ward Upham)

Vegetables:
Rotation of Vegetable Crops

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Rotating vegetable crops is a standard way of helping prevent disease from being carried over from one year to the next. Rotation means that crops are moved to different areas of the garden each year. Planting the same crop, or a related crop, in the same area each year can lead to a build-up of disease. Also, different crops vary in the depth and density of the root system as well as extract different levels of nutrients. As a rule, cool-season crops such as cabbage, peas, lettuce and onions have relatively sparse, shallow root systems and warm-season crops such as tomatoes, peppers and melons have deeper, better developed root systems. Therefore, it can be helpful to rotate warm-season and cool-season crops.
 
As mentioned earlier, it is also a good idea to avoid planting closely related crops in the same area as diseases may be shared among them. For example, tomatoes, potatoes, peppers and eggplant are closely related. Also, broccoli, cauliflower, cabbage and brussels sprouts share many characteristics in common. Therefore, do not plant cabbage where broccoli was the previous year or tomatoes where the peppers were.
 
So, why is this important to bring this up in the fall?  Now is the time to make a sketch of your garden so that the layout is not forgotten when it is time to plant next year. (Ward Upham)

Ornamentals:
Planting Trees in the Fall

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The fall season can be an excellent time to plant trees. During the spring, soils are cold and may be so wet that low oxygen levels inhibit root growth. The warm and moist soils associated with fall encourage root growth. Fall root growth means the tree becomes established well before a spring-planted tree and is better able to withstand summer stresses. However, certain trees do not produce significant root growth during the fall and are better planted in the spring. These include beech, birch, redbud, magnolia, tulip poplar, willow oak, scarlet oak, black oak, willows, and dogwood.
 
Fall-planted trees require some special care. Remember, that roots are actively growing even though the top is dormant. Make sure the soil stays moist but not soggy. This may require watering not only in the fall but also during the winter months if we experience warm spells that dry the soil. Mulch also is helpful because it minimizes moisture loss and slows the cooling of the soil so root growth continues as long as possible. Evergreens should be moved earlier in the fall than deciduous plants. They need at least six weeks before the ground freezes for the roots to become established. (Ward Upham)

Miscellaneous:
Adding Organic Materials Directly to the Garden

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If the summer weather has brought an early end to your garden, consider adding organic materials directly to the soil rather than composting. Materials such as residue from lawn renovation, rotted hay, or rotted silage can be added and then tilled in. Coarser materials such as tree leaves or garden residue should be shredded. A lawn mower with a bagging attachment can be used to shred this material and collect it in one operation.
 
Organic materials can be spread to a depth of about 3 inches and tilled in. Be sure the soil is not too wet before tilling. During warm weather, the material will decompose quickly and the process can be repeated every two weeks. Later in the fall, it may take longer. This process can be repeated from now until late November to early December.
 
Remember that organic matter helps almost any soil. It improves clay soil by improving tilth, aeration and how quickly the soil takes up water. In sandy soils, it acts as a sponge by holding water and nutrients. (Ward Upham)

Moving Houseplants Inside for the Winter

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Many people with houseplants move some of them outside for the summer to give them better growing conditions and help them recover from the stress of an indoor environment. But as fall approaches and night temperatures approach 50 F, it is time to think about bringing plants inside for the winter. Plants that have spent the summer outside should be inspected for insects and disease before bringing them inside. A sharp spray from a garden hose can remove insects or mites from houseplant foliage. Insects in the potting soil can be forced out by soaking the pot in a tub of lukewarm water for about 15 minutes.
 
Houseplants that have been kept outdoors are accustomed to receiving much more sunlight than they do indoors. So how do we help houseplants acclimatize to the lower light levels inside? Houseplants brought in from outside should be started out in an area of the home that receives plenty of light, and then gradually moved to their permanent, darker location. This process should take four to eight weeks depending on the degree of difference in light levels between the initial and final location of the plant.
 
Understanding plant processes allows us to anticipate potential problems. Acclimatization gives houseplants a greater chance of retaining leaves and avoiding the stress of completely replacing them. (Ward Upham)

Pests:
Itch Mites are Back

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Last year was a bad year for itch mites. It looks like 2016 may be bad as well.  These arthropods are responsible for painful bites that result in itching on people. The mites are barely visible to the naked eye but their bite results in a noticeable raised red area with a centralized blister. It normally takes 10 to 16 hours for itching to start after exposure. Unlike chigger bites which are usually restricted to areas where clothing is tight such as belts, underwear or socks, oak leaf itch mite bites appear where clothing is loose such as at the neck, shoulder and chest.
 
Oak leaf itch mites feed on insect larvae living within straw, seeds and plant galls.  In recent outbreaks, itch mites have been feeding on midge larvae which cause gall formation on the margins of certain oak leaves.  Pin oaks are most likely affected but red oaks and black oaks can also act as a host for the midges. The female mite is able to enter the gall through small openings and paralyze the midge larvae with a neurotoxin.  The midge then acts as a food source for the mite allowing her to develop about 200 offspring. It takes about a week for the new mites to emerge. Only about 5 to 10 percent of the progeny are males. The males do not feed but mate and then die.  Females seek new hosts on the existing tree but can be carried by winds for hundred of yards. Mite populations appear in late July and continue through the summer and into the fall.
 
No effective control has been found. Deet-based repellents have not given consistent results. Tree sprays are ineffective as the mites are protected by the galls.  Oak trees known to be infested with mites should be avoided. If work must be done near oak trees with marginal leaf gall, bathing and changing and washing clothing is recommended. This article was adapted from our publication MF2806, “Oak Leaf Itch Mite.” (Ward Upham)
 
Contributors: Ward Upham, Extension Associate

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    Authors

    Ward Upham runs the Horticulture Response Center in the Department of Horticulture and Natural Resources at Kansas State University. Other contributors include K-State Extension Specialists.

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