Rick Durham, Consumer Horticulture Extension Specialist, University of Kentucky
 

Is my baldcypress tree dead?

I had a question recently about a baldcypress, Taxodium disticum. The situation was that someone purchased and planted a baldcypress last spring which grew great during the summer. Come fall, all the leaves on the plant unexpectedly turned brown and quickly fell from the tree. The question to me was, "What should I do with this tree? Hook a chain to it with my truck and pull it out?" No, Wait!!! What this person describes is perfectly normal. The situation sounds healthy to me. Bald cypress belongs to the conifer order of plants along with other familiar species such as junipers, pines, and yews. Many plants in this family have needle shaped or awl shaped leaves, the seeds are produced in cones, and many including baldcypress are the source of valuable timber. Most of these plants also share another characteristic, evergreen foliage. Not so the baldcypress. Come autumn the leaves will turn an orange-brown and fall from the tree. So, actually I would be more concerned if the baldcypress had retained its foliage through the fall and winter. This tree makes a very nice landscape specimen and is particularly well-suited to wet areas, although it will also perform well in dry areas. In wet soils the root system will develop the characteristic cypress knees that have been the subject of many road-side craft shops throughout the southern states. The soft green foliage is attractive in summer, and the reddish brown bark is very attractive in winter. The tree also has few pests although mites may sometimes be a problem, and soils of high pH may promote chlorosis or yellowing of the foliage. Trees are best transplanted while small because they tend to develop a strong taproot that renders them difficult to move when older.
 

Iris borer - let the clean-up begin!

Bearded iris is one of my favorite perennial flowers. I love the tremendous variety of flower color and especially the hot bi-color flower types. Unfortunately, irises are very susceptible to an insect called iris borer that is difficult to control once it is established in the plant. If you have iris in your flower garden, you have likely encountered this pest. Early spring is the best time to take preventative measures to combat this insect. Let's back up a bit. Once fat and mature from feeding on an iris rhizome all summer, the borer larva (worm) leaves the rhizome and enters the soil where it forms a pupa. The pupal stage lasts for two to three weeks and then an adult moth leaves the soil in September or October. The female moth lays eggs on dead iris leaves where they will spend the winter. Come spring, around April or early May depending on how warm the spring, the eggs hatch to produce young larvae that begin on the young, rapidly growing leaves. This should give us a hint as to a possible control strategy. One key practice to borer control is to clean up the dead, egg-containing iris leaves in fall, winter, or early spring before the eggs have an opportunity to hatch. This would be the first line of defense against iris borers and the cleanup should be finished by early April. Also, watch the new growth closely for any sign of sap, scaring, or tunneling that would be associated with early borer feeding. If any is present, squeeze the leaves between your thumb and forefinger near the signs of tunneling to squash the insect inside, or prune away affected leaves before the borer can reach the rhizome. If wilting of entire fans of leaves is noticed later in the season, inspect the rhizomes for soft rot. If present, cut out any infected rhizomes and clean your cutting tool between cuts to avoid spreading the soft rot bacterium to the next rhizome. It is also crucial to inspect plants at the time of dividing to ensure that no borers are being carried along with the new plants. Again, cut away any damaged or suspicious areas and disinfect your knife between cuts. Dipping or spraying your knife in a household disinfectant, such as Lysol, will work well and should also cause little damage to your cutting tool. A 10% bleach or rubbing alcohol solution will also work but may corrode metal utensils. By practicing sanitation such as this in the landscape, many pests can be kept in check will a minimal use of chemicals.
 

Remove bagworm cases from plants.

Early spring is a great time to inspect plants for bagworms. These caterpillars spend most of their lives encased in a cocoon-like case which makes them somewhat difficult to control with conventional insecticides. During winter, these cases contain thousands of eggs which will hatch in spring to produce the next generation of these pests. Bagworms will feed on a wide range of plant species but are most often found on evergreen trees and shrubs such as junipers and arborvitae. The brown cases are fairly easy to detect against the green foliage. Remove the cases by sharply pulling them away from the foliage, or if you prefer, use hand pruners. If hand pruners are used, resist the urge to pull the case with one hand and cut with the other. This will put your fingers very close to the sharp blades of the pruners. Rather, hold a box or can beneath the case as you prune and allow the severed case to fall into it. This will keep your fingers out of harm's way.

Once removed, dispose of the cases in the trash or burn them. Eliminating these cases in early spring before warm weather has a chance to promote hatching of the eggs will help reduce the number of bagworms present later in the season. If you didn't get all the cases, the eggs usually hatch in mid to late May. Young bagworms may be evident eating on foliage at that time. If you see them, treat immediately as this is when they will be most venerable to insecticide. Check with a garden center professional or your county agent for a list of chemicals that would be effective.
 

Fruit sprays-the first few applications are the most important.

If you have fruit trees in your home landscape, you must plan some sort of pest management strategy. Otherwise these trees will become a burden and attract all sorts of unwelcome pests to the yard. Hopefully, your home orchard contains varieties with at least some natural pest resistance which may greatly reduce the number of sprays you must make to the trees. Good cultural management including proper pruning, watering, fertilization, and sanitation will also reduce the amount of sprays needed. However, there really must be some sort of spray program to achieve good quality fruit and reduce the amount of fallen rotten fruit and wasp and bees at the end of the season.

Conventional spray programs begin with a dormant oil spray in later winter or early spring, followed by sprays throughout the growing season at roughly two-week intervals. Several organic alternatives are available for use and these follow similar schedules. The spray applications at the beginning of the season are most important. Following the recommended spray program between bud break (or when green tips are first evident) and petal fall (or when flowers have been shed from the branches) will eliminate most early pests and so reduce the number of pests throughout the season and may make spraying later in the season an option depending on how many pests are present.

For your safety and to protect the environment, always apply chemicals according to label directions. Following these guidelines will greatly increase the amount of useable fruit at the end of the season. For more information, contact your county extension agent and request a copy of ID-21, Disease and Insect Control Programs for Homegrown Fruit in Kentucky Including Organic Alternatives - 2001.
 

Things to do in April:

• Sow seeds of cool weather crops including beets, turnips, carrots, Swiss chard, onions, and peas, as soon as the soil can be worked. Plant seed potatoes and transplants of cole crops including broccoli, cabbage, Brussel sprouts, and kohlrabi.
• Sow seeds indoors of flowers and vegetables for transplants if you have a sunny window (preferably south-facing) or in a hot bed or cold frame. Start most plants about six weeks before they will be transplanted outdoors. Melons, cucumbers and pumpkins are usually ready for transplanting four weeks after seeding indoors.
• Begin an insect and disease control program for fruit trees.
• Remove excess mulch from perennials as new growth begins.
• Check the lawn mower and other garden equipment and tools and perform needed repairs and maintenance.
• Remove and destroy bagworm cases from landscape plants. Each case contains hundreds of eggs. By eliminating the eggs now you may reduce the number of bagworms later in the season.
• Plant gladioli weekly beginning in late April to have a steady supply of cut flowers through the summer.
• Begin preparing the garden and flower beds for planting once the soil is dry enough to work. If you squeeze a handful of soil and it forms a muddy ball, the soil is too wet. If it crumbles apart when you open your hand it is dry enough to work. Remember to add organic matter and needed lime and fertilizer and you work the soil.