Extension Educator, Local Food Systems and Small Farms
Extension Educator, Horticulture
April 30, 2009
Mulching is a sure-fire way to eliminate many summer gardening chores, states David Robson, University of Illinois Extension horticulture educator, Springfield Center.
The primary benefit of mulching is to reduce soil water loss or evaporation. This means more water is available to the plants, which means less wilting problems.
Typical soils can lose a quarter to half inch of water per day when temperatures are above 90 F. Since most plant roots are in the top 8 inches of the soil profile, plants suffer greater wilting stress when temperatures are high.
Mulching also keeps the soil cooler during warm spells. Mulches act like insulation, preventing hot air from reaching the root system. Roots grow better when soil temperatures are in the 60s and 70s; proper mulching can maintain this desired level when air temperatures approach 100 F.
Weed control is another added benefit of mulching, adds Robson. Most weeds need sunlight after germination to grow. Mulching limits sunlight reaching newly germinated seedlings. Fewer weeds mean less competition with plants for water and nutrients.
Vegetable gardeners should realize that mulching limits some diseases, especially fruit rots. Most disease organisms are transferred to plants or their fruits by raindrops splashing on the soil and bouncing back up. Mulching deflects water droplets from "bouncing" back and infecting the plants. Produce commonly in direct contact with the soil—such as cucumber, melons and even tomatoes—are less likely to be infected by disease organisms when mulched. Mulching also increases the ease of harvesting, especially after heavy rains or irrigation.
Proper mulching consists of no more than 2 to 4 inches of an organic material such as wood chips or composted leaves and grass clippings. If you use cocoa bean hulls, which can lead to problems with dogs if they eat it, limit yourself to 1 inch. Heavy applications of cocoa bean hulls tend to mold.
Deeper levels of mulch may inhibit water and air penetration into the soil or tend to compact. Shallow mulching reduces the benefits of weed control, cooler soil temperatures and water retention.
Ornamental plants such as flowers, shrubs and trees benefit from 4 to 6 inches of mulching. However, make sure to keep mulching material an inch away from tree and shrub trunks to minimize insect and disease damage.
April 28, 2009
April 28, 2009
Everyone seems to have been waiting for warmer temperatures, and the appointed date, to begin broadleaf weed control programs. Well that time will come, believe it or not. We have also been waiting for a period of drier conditions with lighter winds. For most of the broadleaf products to work, the temperature has to be over 55 degrees. These chemicals do work better when it is warmer and the weeds are actively growing.
The first item of business is to know what type of weeds you want to control. This will make a big difference in what product, or products, you select.
The main products used for broadleaf weed control in lawns are 2,4-D, MCPP (mecoprop), dicamba, a combination of those three products, and triclopyr alone or in combination. Let's start with the triclopyr since it's probably the easiest to discuss. Its place in weed control is for hard to control weeds and woody plants. It also improves control of violets. It can be added to one, or more, other chemicals to provide broad spectrum control. Some blends now contain trichlopyr, so check the label under active ingredients.
2,4-D is the old standby. It is good on carpetweed, chicory, dandelion, lambsquarters, plantains, and wild carrot. MCPP is good on chicory, lambsquarters, and white clover. Dicamba is good on black medic, chickweeds, chicory, dandelion, dock, henbit, knotweed, lambsquarters, pearlwort, purslane, red sorrel, thistles, white clover, wild carrot, and yarrow. The combination of all three products will pick up all of those listed for the individual products, plus a few more such as mallow, speedwell, and wild onion. The combinations are sold under many different trade names, so check the active ingredient list for ones you need.
My annual disclaimer for application of these types of products is: "Beware of potential drift from these products." Not only can the spray move under windy conditions while you are spraying, but particularly with dicamba, the products can drift as a vapor for up to two weeks after spraying with hot and humid conditions. There are amine, low volatile ester, and ester formulations of many of these products. The amines are water soluble and don't vapor drift as much. The ester forms are much more likely to vapor drift, but also penetrate weed leaves better.
Weeds can also be an indicator of turf condition. Around here, crabgrass and white clover may be an indicator your mowing height is too low. Most cool season grasses should be mowed at a minimum of two inches tall. If you have an abundance of these weeds, try mowing a half inch higher. Of course, these same weeds tend to fill in spaces where turf grasses are absent.
April 21, 2009
The West Central Region has designated April 19-25 as Extension Week. Logan County has had Extension since February of 1918. It began with a Farm Advisor named Elmer Ebersol who began selling the county memberships in the combined Extension and Farm Bureau system that remained in place until the 1950's.
Early projects included establishment of the county Pure Bred Live Stock Breeders' Association, Pure Bred Beef Cattle Breeders' Association, Pure Bred Dairy Cattle Breeders' Association, and the Pure Bred Swine Breeders' Association. Soybeans were a new crop at that time, and their planting was being encouraged. Of course, soybeans were used mainly for hay in their early years. Spring wheat was the predominant wheat crop of the time, and there were several thousand acres of oats. Farm labor was a major concern of the time, and labor placements were a major focus of Extension. The first soil survey of the county was also begun.
The 4-H Program began about 1920 with the first 4-H Clubs focusing on specific projects of swine and corn. Later in 1923 there began a push for home economics based clubs, and the push was on to identify volunteer leaders. Home Economics was added a few years later with the first "Home Advisor." Focuses were on running a household and home food preservation.
Logan County added an aggressive Community Resource Development program in the late 1970's. This program was responsible for many of the community wide surveys done in the early 80's, and these surveys even led to removal of the city of Lincoln parking meters around the square and municipal parking lots.
Extension continues to evolve as needs of residents change. Horticulture programming became more prevalent in the 1980s, non-traditional youth programs such as school enrichment and special interest clubs began in the 1980's, and the Family Nutrition Program started in the 1990's. Web pages began to be a communication medium in 2003, and today there is an average of about 15,000 hits per month on county web pages.
Extension Week helps us remember where we have been, and to focus on being of value to local citizens. Extension has always been blessed with many exceptional volunteers, and today is no exception. There are over 100 volunteer leaders in the 4-H program, and many others serving on committees and councils for various programs. If you are interested in volunteering, please feel free to contact the office at any time.
April 21, 2009
Early in the spring, there are many pest that become active. Many of these are timed by the saucer magnolia blooms, according to Orton's "Coincide" book. The past week or so, when the magnolia blooms were in the pink-bud stage, spruce spider mites became active. These mites are one of the major downfalls of spruce in our area.
To determine if you have spruce spider mites, hold a piece of white paper under a branch and shake it. The mites will look like moving dust specks on the paper. Many times, there will be some fine webbing, like spider web, visible on the needles as well.
Spruce spider mites can be controlled with sprays of acequinocyl, bifenthrin, cyfluthrin, insecticidal soap, or summer oil spray. The soap or oil sprays will require a second application about a week later to give good control. These mites normally remain active until mid-May, but the cool conditions thus far may extend their life cycle this year.
Other spring pests are also indicated by the saucer magnolia. During the bloom stage, going on now, the ash plant bug, fall cankerworm, spring cankerworm, Fletcher scale, leaf crumpler, eastern tent caterpillar, juniper webworm, and Zimmerman pine moth are susceptible to control. As we get to the petal fall stage, European pine sawfly, Gypsy moth, hawthorn mealybug, honeylocust pod gall, and willow aphid become susceptible to control.
April 21, 2009
April 17, 2009
Now that most of our spring flowering shrubs and trees are finished blooming, it is time to prune them so they will flower on schedule next spring. These plants bloom best and can be kept in bounds with annual pruning.
Since early flowering plants bloom from buds set the previous summer, prune now so plants have plenty of time to set buds for next spring. Begin by removing all dead or broken branches.
Multi-stem flowering shrubs can become too tall and bare at the bottom. They can be renewed by cutting out a number of the oldest stems to the ground each year. This stimulates new growth from the roots. Cut out 1/4 of the oldest stems all the way to the ground. Renewal in this manner keeps the plant quite free of borers and scale insects and the oldest stems will be only four years old.
Old plants may have only a few main stems. The immediate result of renewal on these plants may be somewhat unattractive. But new shoots from the bottoms of the plant will provide a better shape and foliage to the ground. Then future renewal pruning will result in no loss of beauty.
Stems remaining from renewal pruning are often too long and ungainly. Therefore, single stem plants and small flowering trees may be headed back. Head back overly long branches by removing them to a shorter side branch that grows in the same direction or away from the center of the plant. The result will be a smaller plant, but it won't change the character or shape of the plant.
Flowering trees and single stem shrubs are often grafted on different rootstocks. Remove any suckers that are growing from the ground. Also flowering trees bloom best on horizontal branches. Remove any strongly vertical water sprouts that shoot up through the center of the tree before they take over.
Most people are afraid to do any pruning on their plants because they think it will harm them or because they are afraid to make a mistake. Pruning actually stimulates plants to grow, making them more vigorous and healthy; they flower better. Plus, plants continue to grow; so if you make a mistake, in a season or so when the plant has recovered, you can do the pruning again the right way.
Do not be afraid to experiment. Plants are very forgiving. They can take quite a bit of abuse and come back faithfully to provide enjoyment and beauty in our garden.
April 14, 2009
A common maintenance chore in a perennial garden is that of dividing. There is no set rule as to when to divide perennials. Some may need division every 3-5 years, some 8-10 years and some would rather you not bother them at all.
Perennials will send signals to let you know that they would like to be divided. The signals to watch out for include: flowering is reduced with the flowers getting smaller; the growth in the center of the plant dies out leaving a hole with all the growth around the edges; plant loses vigor; plant starts to flop or open up needing staking; or it just may have outgrown its bounds. These are the signs to look for and not a date on the calendar.
If division is indicated, spring is the preferred time to divide. Some fleshy rooted perennials such as poppy, peony, and iris are best divided in the late summer to very early fall.
Division is usually started when growth resumes in the spring. The process starts by digging around the plant and then lifting the entire clump out of the ground. Then, using a spade or sharp knife, start to cut the clump up so that each clump is the size of a quart or gallon sized perennial.
Discard the old, dead center and trim off any damaged roots. The divisions should be kept moist and shaded while you prepare the new planting site. After replanting, water well and protect the divisions from drying out. Division is no more complicated than this. Some perennials may be more difficult to divide than others because of their very tenacious root system. Division has as its primary goal the rejuvenation of the perennial planting, so it can continue to perform the way it was intended. Many home gardeners have found that the process of division is more traumatic to the gardener than it is to the perennial.
April 14, 2009
The spring mowing season has begun for some, and will shortly for the rest of the people. We are running a couple of weeks behind normal as for the starting time, but soil temperatures retreated about 10 degrees in the last 10 days. There is certainly enough moisture, so add a little bit of heat and we'll be hard pressed to keep up this spring.
There are a few very simple rules for mowing grass. The first is to use equipment that is ready for the job. Make sure the mower has sharp blades. Dull blades will show up as injury on the grass blades like brown tips and jagged edges. Blades can be sharpened in several ways. Using a file or grinder are the most common methods.
Next is the rule of one-third. Never remove more than one-third of the leaf blade at any one time. This rule must be followed if you don't want to catch, or rake the grass. A good general mowing height for combination bluegrass and fine fescue is about two inches. This would mean that you would need to mow every time the grass reached three inches in height.
Bagging grass clippings may actually add to the build-up of thatch (that dead matted layer on the soil surface). Thatch is broken down by microbes at the soil surface. Without a food source, the microbe numbers crash, and any clippings remain, without breaking down. The variety of grass also has a lot to do with the thatching tendency.
Mulching is OK. It isn't a cure-all, and it does take quite a bit of extra power to accomplish. The final word is that grass mowed on the on-third rule doesn't need to be caught or mulched. Bagging takes time and the clippings must then be disposed of. Mulching takes extra power and fuel.
Mowing intervals depend upon grass growth rather than a calendar schedule. The spring and fall periods will require more frequent mowing than during the summer. That is in a "normal" year. Mowing frequently really reduces the labor needed for overall operations.
April 14, 2009
April 8, 2009
With alternating warm and cool (or cold) weather, we see many nuisance pests when we get the warm days. We've been through the second round at least, and I'll guarantee at least one more round this spring. Add to that the fact we are active on the warm days, and we are doing things like destroying their resting places by cleaning off flower beds and raking up piles of leaves.
Let's start with the Asian ladybugs. Right now they are alternating between resting and sunning, weather dependent of course. These are the beetles that overwintered as adults, and are looking for a place to stay and something to eat. We've already had a round or two this spring, and we're sure to have more with the type of weather we've experienced. Sunrooms, porches, and windows are the obvious collection points for the beetles. The best control in the home is a vacuum cleaner. If you have numbers too large for that control, area sprays of an aerosol flying insect killer will knock down the ones it hits. If you are terribly bothered, try a perimeter spray of the foundation, door areas, and window areas on the home with a pesticide that will last for a while. Color test the material on siding first, and hope for the best. The pesticides are effective, but they are sometimes overwhelmed by the number of ladybugs that you are trying to control. Permethrin and bifenthrin are probably the most commonly used pesticides for perimeter sprays.
A common home invader over the past several weeks has been the millipede. Millipedes are hard shelled animals that are worm-like with many segments. They also curl up when disturbed. Most body segments have 2 pair of legs, except for the 3 behind the head. Adults are 1-2 inches long and can be brown, tan, or gray. Most millipedes are scavengers. They feed on decaying organic matter such as leaves, compost, and grass clippings. They may sometimes injure small, young plants by feeding on the roots and tender plant parts, but this is rather rare.
When they enter the home in large numbers, they can become quite a nuisance. They do not bite, feed on clothing, or cause any real damage. They are simply a nuisance. Control of millipedes in the house is best accomplished by running the vacuum cleaner. Most insecticides are not very effective against millipedes. The best way to prevent them from entering the home is to remove and discard accumulations of leaves, rocks, boards, and other trash from around the foundation of the house. Also, keep shrubbery and flower beds free of leaf mulch during the warm months. Foundation sprays of permethrin or bifenthrin may have some effectiveness, but they may not provide satisfactory control. To apply these sprays, spray the foundation of the house and the adjacent foot of soil. In severe cases, you may need to expand the soil treatment area (and maybe spray the entire yard).
Also with some warmer weather comes the swarms of insects that raise that perennial question of "Are they ants or termites?" Swarming time for both insects is about the same time, and they are really looking to start new colonies because they have outgrown their old ones. This is the reason for the winged insects, the wings allow the ants or termites to cover larger areas to start their new colonies. The differences between ants and termites are several.
Let's start with the body color. Termites are always blackish in color, while ants may be black or other colors. If you have winged insects that are not black, you don't have termites. Next, look at the body shape. Ants have a constricted "waist" while termites don't have that classic hour-glass figure. Antennae and wings are the other two body parts to look at. Antennae on ants are elbowed, basically in an "L" shape, and those on termites are straight. Both ants and termites have pairs of wings, but termite wings on the same side will be of equal length, while ant wings are of different lengths on the same side.
April 7, 2009
Spring is barely two weeks old, and we are about to experience how fickle Mother Nature can be. If the forecasters are correct, very cold air will move through Illinois.
"Just last weekend I was commenting on how many buds my tree peony had, anticipating the large, beautiful fragrant blooms that will cover the plant," says Martha Smith, University of Illinois Extension horticulture educator. "With temperatures forecasted to dip below 30 degrees, I wonder if they will survive."
We have been spoiled with early warm temperatures. But, patience this time of year is so important. Average dates of last frost range from April 5 in southern Illinois to April 25 in northern Illinois. That means we still have a 50 percent chance of freezing temperatures.
"We usually recommend a 2-week waiting period before it is declared 'safe' to plant," says Smith. "But, I remember May 3, 2005, when night-time temperatures in western Illinois dipped to 28 degrees --- Mother Nature's way of reminding us of who is in charge!"
There are two types of freezes, radiation and advective.
Radiation freezes or frosts occur on calm, clear nights when heat radiates into the environment from surfaces or objects. Soil, buildings, plants and other objects at the earth's surface act as a heat reservoir by absorbing heat during the day. Plants are damaged when enough heat is lost from this reservoir to lower the temperature at the surface to below critical temperatures. These freezes are generally considered light, and they primarily damage outer tips and expanded buds. Plant damage from a radiational freeze can be minimized by reducing radiant heat loss from plant and soil surfaces.
Advective freezes can occur when cold air masses move down from northern regions, causing a drastic drop in temperature. Windy conditions are normal during advective freezes. Although radiant heat loss also occurs during an advective freeze, Smith says the conditions are quite different from a radiation freeze. The temperatures tend to be much lower and are liable to last longer during advective freezes, and protecting plants is more difficult. Expanded buds and new leaves will be damaged. Tip die-back may occur. Herbaceous plants may be killed completely or die back to ground level.
Plant protection during radiation freezes involves covering plants to prevent heat given off by soil and plants from escaping into the atmosphere. Protective coverings are usually porous material such as newspaper, bed sheets or burlap.
"Use stakes to hold the covering up and off the plant material," advises Smith. "Boxes, buckets, styrofoam containers or milk jugs with their bottoms removed can also be placed over plants to help alleviate heat loss."
April 3, 2009
If your lawn is overly shaded and has poor drainage, moss may be a problem. Moss is a fast-growing, shallow-rooted plant that covers the ground, smothers grass and exhausts food reserves from the soil.
When moss appears in a lawn, it is usually because growing conditions for grasses are adverse, such as overly shaded or moist areas of the lawn, states David Robson, University of Illinois Extension horticulture educator, Springfield Center. Other conditions favorable for moss invasion include soils with poor aeration, compaction or drainage, low fertility and high acidity or alkalinity. To control moss permanently, conditions that allow its growth must be eliminated.
Because shade is a major cause of moss growth, you might want to prune some of the trees surrounding your lawn. Removing lower branches and thinning the crowns of large trees will also help.
Improve your lawn's drainage by filling depressions, redirecting downspouts and adding tile. Slicing or core cultivating will improve aeration or reduce compaction.
Mechanical devices such as aerifiers, core cultivators and vertical mowers can be rented at local rental stores.
Test the soil pH to make sure your lawn is not too acidic or alkaline for the variety of turfgrass grown. Incorporate needed amounts of fertilizer and lime or sulfur to correct the soil pH.
In addition, raising the mower cutting height to 2 1/2 or 3 inches will improve the vigor of the grass and will help shade out moss.
Moss can be temporarily removed by raking or can be chemically killed by thoroughly soaking the moss with a ferrous sulfate solution at 5 pounds per 1,000 square feet of lawn. Dead moss may be removed by raking, and bare areas can be reseeded.
Where conditions are not corrected, moss will continue to grow.
April 1, 2009
We are now on the books with the first snow of spring. Two to four inches of the white stuff, but at least it didn't last long. We really won't have any ill effects to plants from the snow, quite the contrary, as it provided an insulating blanket for everything. Grass and early garden plants look better after the snow than two days ago. Of course we can do without any more for this season. The main problem is the moisture accompanying the storm. Soil will be too wet to work for several days now, and this fact can put us a little behind on the gardening calendar. Don't worry, unless the trend is prolonged. Heat units accelerate as we approach the summer months, and many crops catch up quickly.
April 1, 2009
Each year, the winter annual weeds chickweed and henbit run number one and two in the early spring. This year is seems like henbit is running slightly ahead. Winter annual weeds can actually germinate in the fall, carry through the winter, then get going very early in the spring. They also are done by the heat of the summer, leaving seed to germinate again later in the fall. Right now chickweed stands out in yards because it is quite abundant, and has a lighter green color than grass and most other weeds. I can't begin to tell you how to identify it, it gets even harder when there is common chickweed and mouse-ear chickweed. Henbit is easier to identify since it has purple flowers and smells like mint. As for control, that gets a bit easier.
The straight 2,4-D that is used on dandelions seems to act like a fertilizer for chickweed and other problem weeds. Combinations that contain 2,4-D, MCPP, and dicamba are rated very effective on chickweed, henbit, red sorrel, purslane, white clover, and others. Just remember the control time for most broadleaf weeds is early May. These combinations are sold under several different trade names. You can find these at most hardware, discount, and lawn and garden stores. Just check the label under active ingredients and check for two long chemical names and dicamba. You can also check to see that it says it will control chickweed and henbit. This group of chemicals is effective in the 50 degree range and up. As with any chemical control, read and follow label instructions very carefully. There will be some cautions on these product labels concerning injury to sensitive plants that you should be aware of. This is because dicamba can drift as a vapor for a few weeks after you apply it if the weather gets hot and sunny.
April 1, 2009
One of the main things to discuss today is the removal of nuisance fruit. You may be thinking about those apples or peaches, but really the nuisance fruit category includes things that are much more a nuisance like sweet gum balls, maple seeds, and crabapples.
There are several products available to eliminate nuisance fruit. The most common is ethephon, and it is used as a foliar spray to reduce or eliminate undesirable fruit or seeds. Some of the trade names include Florel and Ethrel. The product is effective at eliminating much of the fruit without affecting leaf growth and color, and it does not harm other plants that get some spray drift on them. It also does not affect the actual flowering of the treated trees.
With ethephon, the key is in the timing. The application must be made during flowering, but before the fruit set in. For most flowering trees there is a 10-14 day window of opportunity. Sweet gums are a little tricky since there are no showy flowers involved, so effective sprays should occur just as new leaves begin to emerge. Sprays should leave leaves wet, but not to the point of dripping. Good coverage of the tree is needed, so keep in mind the size of the tree when you are weighing this option. There are injectable products available, but must be applied by a professional. The injectable products have not been as effective as the sprays.
This product is a growth regulator that naturally occurs. Its natural production is stimulated by stress, so make sure you aren't treating a tree that is under stress from drought, high temperatures, diseases, or other environmental stresses. Treating stressed trees can cause severe injury to the plant such as leaf loss or scorching.