Yard & Garden Line News Volume 8 Number 8                                                               June 1, 2006

Features this issue: Get My Drift--Legal Aspects of Pesticide Drift Insurance Coverage and Damage Caused by Trees 2006 Herb of the Year---Scented Geraniums Wet Weather Brings Out the Fungi Crane Flies Cutworms in Lawns Azalea Sawflies Garden Calendar Editorial Notes

Get My Drift--Legal Aspects of Pesticide Drift
Lorrie Stromme, attorney and Hennepin Co. Master Gardener

2,4-D damage to green ash Photo credit: Beth Jarvis

Every year, nearly 5 billion tons of pesticides are intentionally applied to the American landscape¹. Responsible pesticide use is critical to avoid adverse environmental impacts. At the neighbor-to-neighbor level, the issue can become contentious when pesticides drift from one neighbor's yard to another. The following answers address homeowners' most commonly asked questions about pesticide drift.

1. What is a pesticide?
Federal law defines a pesticide as any substance intended for "preventing, destroying, repelling, or mitigating any pest," and substances intended for use as a plant growth regulator, defoliant, or dessicant². The word-ending "cide" means "killer." The term "pesticide" is a general term and includes insecticides (killer of insect pests), herbicides (weed control), fungicides (fungi control), rodenticides (mice/rat control), etc.

2. What is pesticide drift?
Pesticide drift is the movement of pesticides through the air, away from the area where they were applied. It's somewhat analogous to secondhand smoke. Cigarette smoke drifts away from the smoker and can be inhaled by nearby non-smokers as secondhand smoke. Similarly, a herbicide sprayed on a plant or tree can drift away from its target and land on non-targeted plants. Drift becomes a problem when the herbicide or other pesticide has an unintended impact or causes damage. An example is 2,4-D, a herbicide used to control dandelions and other broadleaf weeds. Some lawn-care products (e.g., Ortho Weed-B-Gon and Scotts Turf Builder with Plus 2 Weed Control) contain 2,4-D. The granular form of 2,4-D can turn into a gas and drift away from the place where it was applied, harming plants sensitive to 2-4-D, like grapes, tomatoes, and lilacs³.

3. How can pesticide drift be prevented?
Preventing spray drift is the responsibility of the person applying the pesticides. (Applicators include private citizens, farmer/growers, commercial applicators, and non-commercial applicators.) Using common sense is the best means of prevention. Mix and apply pesticides only when winds are calm (less than 10 mph). Most important, read the label on the pesticide before using it, and follow the directions. The label is the law. All of the label directions are the legal requirements for using the pesticide safely and effectively. Pesticides must be applied correctly to avoid collateral damage. Pesticide labels are not an easy read; they take some time to review and understand. But it's time well spent … to use pesticides responsibly and to stay on the right side of the law. Pesticide labels can be found on the internet, if the label attached to the product is hard to read.⁴

Pesticides can be used only on the sites, plants, or crops listed on the label. The label also specifies the application rate and method, storage and disposal information, protective clothing to wear while using the pesticide, and environmental hazards (e.g., "toxic to bees").

Herbicide injury to Ural false spirea Photo credit: Beth Jarvis

4. Will the vegetables and fruits in my garden be safe to eat?
If a pesticide that drifts onto your vegetables or fruit is not labeled for use on vegetables or fruit, do not eat them. Pesticides that are labeled as safe to use on particular vegetables and fruits identify "safe" levels of pesticide residue for the food-plants listed on the label. But there is no sure way to know if a pesticide labeled for use on a non-food plant has a "safe" level of pesticide residue for a non-target plant. For example, a lawn herbicide can be used on turf, but the label does not identify a safe level of herbicide residue on fruits and vegetables, because they are non-target plants. If you are uncertain, don't eat the affected fruit and vegetables.

5. What can I do if my neighbor uses a pesticide that damages my plants or property?
In Minnesota, it is illegal to apply a pesticide that strays onto the adjacent property and causes damage.⁵ In fact, pesticide drift is illegal even if there is no damage. "A person may not direct a pesticide onto property beyond the boundaries of the target site," according to the law. ⁶

Taking your case to court for the loss of garden plants is not a good option. Most of the cases that have ended up in court involve aerial spraying of acreage (crops or forests) and significant monetary losses. The "garden variety" dispute between neighbors is usually not taken through the trial and appeal process, because of the financial realities of paying for lawyers, expert witnesses, scientific analysis, and other litigation costs. The challenge is proving what pesticide did the damage and the connection between the pesticide that drifted off-target and the damage done. Scientific analysis for pesticide residue is costly (usually several hundred dollars.) The University of Minnesota Extension Service no longer has a clinic or other means to diagnose pesticide drift or herbicide damage in home landscapes. The Minnesota Department of Agriculture (MDA) oversees pesticide use in the state. But the MDA investigates complaints only when it suspects that there is a violation of the law. Priority is given to investigations involving injury/damage to humans, animals, food/feed products, and the environment. The MDA receives complaints at 651-296-6121. The complaint process is explained online at http://www.mda.state.mn.us/appd/pesticides/complaints.htm.

The recommended option is to try the neighborly approach. "My experience has taught me that by far the best way to resolve or prevent drift disputes is for the two parties to discuss the situation as adults in an open and respectful manner," maintains Dean Herzfeld, a University of Minnesota Associate Professor and Extension Educator in the Plant Pathology Department, and the Coordinator for the Pesticide Applicator Training Program in Minnesota. Speak to your neighbors in a friendly, tactful way and explain your concerns about the impact that their pesticide use has had on you, your health, your garden, or your pets. Try to negotiate a solution that satisfies both of you. Find out what pest problems your neighbors are having and provide constructive information about nontoxic, pest-control methods. For instance, if your neighbors use a product containing 2,4-D to control dandelions and it drifts onto your tomato plants, you could provide information about corn gluten meal, an organic alternative for control of dandelions and other broadleaf weeds.⁷

Take a tip from the experts: Use the neighborly approach to deal with your drift disputes and preserve harmony in your neighborhood.

¹ Timothy Kiely, David Donaldson & Arthur Grube, Ph.D., Pesticide Industry Sales and Usage: 2000 and 2001 Market Estimates, at 10 (Biological and Economic Analysis Division, Office of Pesticide Programs, Office of Prevention, Pesticides, and Toxic Substances, U.S. Environmental Protection Agency, May 2004.).
² See 7 U.S.C. § 136 (u)
³ Herzfeld, D, B. Jarvis, The Considerate Gardener's Guide to Pesticides, Part 2. Yard & Garden Line News, September 1, 2003. http://www.extension.umn.edu/yardandgarden/YGLN-Sept0103.html
⁴ See, for example: http://www.cdms.net/manuf/default.asp
⁵ "A person may not apply a pesticide resulting in damage to adjacent property." Minnesota Statutes §18B.07, Subd. 2.3 (b).
⁶ Id.
⁷ U of MN information on corn gluten meal: http://www.extension.umn.edu/extensionnews/2004/gluten.html

Insurance Coverage and Damage Caused by Trees
Lorrie Stromme, attorney and Hennepin Co. Master Gardener

Neighbor drops in. Photo credit: Beth Jarvis

When a tree limb falls off or a tree is blown over and causes damage, you have three options: file an insurance claim, take an income tax deduction for a casualty loss¹ , or file a lawsuit seeking compensation for the loss². This fact sheet deals with insurance.

What does insurance cover?
Most insurance covers two things: damage that you experience (casualty) and damage for which you are responsible (liability).

What is casualty insurance and what does it cover?
When it comes to residential landscape plants (trees, shrubs, lawns, etc.), casualty insurance generally covers losses caused by fire, lightning, theft, hail, vandalism, or other calamities. Landscape losses caused by wind, a tornado, or hurricane may not be covered, except to cover the cost to remove a fallen tree from a house or other structure and have the tree debris hauled away. The insurance policy often puts a cap on this type of loss. For example, the insurer may agree only to pay up to $500 for the removal of the debris from a tree that has fallen. Check you insurance policy for the details of your coverage.

What if my insurance does not cover the loss?
The general rule is that losses not compensated for by insurance or other means can be deducted as a casualty loss on a person's federal income taxes. The Internal Revenue Service defines a casualty loss as "the damage, destruction, or loss of property resulting from an identifiable event that is sudden, unexpected, or unusual." If the loss is caused by progressive deterioration, the loss does not qualify. Landscape plants (trees, shrubs, and other plants) that are damaged or destroyed by a disease, termites, or other insect pests generally do not qualify as a casualty loss, because the damage is progressive rather than sudden.

If, however, the cause is unexpected and unusual, the Tax Court has allowed a tax deduction. In one instance, the Tax Court found that that a black oak tree attacked by two-lined chestnut borer insect died suddenly - within a few weeks - and constituted a casualty loss. The taxpayers in that case were allowed to deduct the amount of the diminished value of their property resulting from the loss of the tree. By contrast, termite damage does not qualify as a casualty loss, because it is not sudden.

What is liability insurance and what does it cover?
Liability insurance covers loss or damage suffered by someone else for which you can be held legally responsible. For example, if a guest slips and injures herself on your home's ice-covered steps, you could be held responsible (liable) for the injury that your guest suffered.

Does insurance determine who is responsible for losses caused by failed trees?
No. A common misconception, even among insurance professionals, is that insurance coverage determines liability. Responsibility for damages (liability) is determined by legislatures enacting laws or by courts deciding cases. An insurance policy is simply a contract to reimburse an individual for losses suffered or caused. For example, if you have a tree in your yard that you know presents a hazard, you will be liable under the law for damage that your tree causes when it falls on a passerby or on your neighbor's property.

View from other side. Photo credit: Beth Jarvis

Insurance may cover all or portions of the loss, regardless of who is responsible or liable under the law. Your neighbor's casualty insurance may pay for the damage to his property caused by your tree. If the person who is hurt by the falling tree has a medical insurance policy, that policy will pay for medical treatment. Since you are liable for all of the damages, your liability insurance will likely cover most, if not all, of the losses. Often people rely on insurance to cover their losses, without considering who is legally responsible. However, there are always limitations on what insurance companies pay. If you have legal liability, you will be responsible to pay what insurance does not cover.

What should I do if my property is damaged by my neighbor's fallen tree, and my neighbor insists that I can recover only from my own insurance company?
If you have questions about your liability, you should contact a lawyer and not simply take the word of an insurance agent. After all, if you get sued, it will be you - not your insurance agent - who has to go to court, attend depositions, take the witness stand, and endure all of the stresses that accompany litigation. Courts decide disputes based on the law, not on insurance coverage.

¹ IRS Publication 547, entitled Casualties, Disasters, and Thefts." See also, 26 U.S.C. 165(c)(3).
² Guide for Plant Appraisal, 8th Edition, Savoy, IL: International Society of Arboriculture (1992).
³ Internal Revenue Code, Section 165.
⁴ McKean v. Commissioner, T.C. Memo 1981-670, 42 T.M.C. (CCH) 1709 (1981).
⁵Rev. Rul. 63-232.

2006 Herb of the Year --- Scented Geraniums
Shirley Mah Kooyman, Adult Education Manager

'White Unique' geranium

'Snowflake'-with white leaves Photos: Shirley Kooyman

The International Herb Association (IHA) has selected scented geraniums (genus Pelargonium), in the Geranium Family (Geraniaceae) as the 2006 Herb of the Year. They are native to South Africa and were introduced to England and the Netherlands in the 1600s. Later the early settlers brought them to North America from Europe. The Geranium Family consists of 11 genera divided into 5 subfamilies. The scented geraniums belong to the subfamily Geranioideae, characterized by having fruit with a beak-like structure that resembles a crane's bill. The genus Pelargonium consists of 280 species, but only about 30 species are cultivated as scented geraniums. The plants are grown primarily for the scented leaves, although some cultivars also have the added bonus of producing pretty flowers. The scented geraniums are classified largely according to their scent with the major categories being: rose-scented (i.e. P. capitatum 'Attar of Rose' = rose), mint-scented (i.e. P. tomentosum = peppermint), fruit-scented (i.e. P. odoratissimum = apple), spice-scented (i.e. P. x fragrans = nutmeg), pungent-scented (i.e. P. quercifolium 'Chocolate mint'= chocolate mint). The scents are released from oil glands located at the base of the hairs. The essential oils are extracted from these oil glands and are used in perfumes and as insect repellents. For culinary uses, the fresh leaves are used to flavor butter, jelly, salad dressing, punch, cookies, cakes, pies and ice cream.

As a group the scented geraniums are easy to grow. They do well in sunny areas with well-drained, rich soil. Depending on the cultivar, the height of the plant can range from one to four feet tall. Some are robust and bushy, others are trailing, and still others are small stature. They are generally free of diseases and insect pests. Propagation is from stem cuttings, since seeds do not come true from cultivars. In Minnesota we have to treat them as tender perennials and bring them indoors when temperatures drop to freezing, since they are not cold hardy.

To learn more about using herbs and scented geraniums, be sure to join us on Saturday, June 17 for Herb Day: Scented Geraniums and other herbs, Saturday, August 12 for Herb Symposium: A Fancy Summer Tea and Saturday, October 14 for Herbal Gifts and Appetizers for the Holidays.



Wet Weather Brings Out the Fungi
Michelle Grabowski, Regional Extension Educator-Horticulture

Ash anthracnose

Oak anthracnose

Venturia on aspen

Leaf curl of cherry

Crown rust All Photos: Michelle Grabowski

Throughout much of the state we have had several days of rain and cool weather. This has provided the perfect environmental conditions for many common leaf diseases, of which we are now seeing the symptoms. New leaf tissue is especially susceptible to disease because it does not have the structural or biochemical defenses that leaves develop as they age. Combine this with a flush of fungal spores being produced in the moist conditions, and we have a complete disease triangle (pathogen - host - environment). Below are a few of the foliar diseases that are developing on trees at this time.

Ash Anthracnose
Ash anthracnose is caused by the fungus Discula fraxinea. Lesions caused by anthracnose are irregular blotches that look water soaked and are brown with a green tinge. Young leaves on the ash tree may appear distorted as the fungus restricts growth of the new tissue. In severe infections, leaves can be completely killed and will drop from the tree. Symptoms typically appear first in the lower branches of the tree, but can occur in the entire canopy when conditions are right. Fortunately ash anthracnose thrives in cool wet weather, so as temperatures rise and trees dry out, the pathogen will subside. As the ash leaves age they will become almost resistant to the fungus and will only be able to become infected when attacked by insects or stressed by heat or other environmental factors. New leaves will grow back on defoliated branches.

Avoiding stress through out the season will help ash trees recover from this early season infection. Water during times of drought, avoid using heavy equipment around the root zone of the tree, and always be careful not damage the tree when mowing. In the fall rake up and destroy all leaves as they can be a source of infection in the following year.

Oak Anthracnose
Oak anthracnose is caused by the fungus Discula quercina. Like in ash anthracnose, lesions of oak anthracnose are water soaked and irregular. In oak, these lesions commonly follow the leaf veins and are tan to dark brown in color. Lesions often cause cupping or distortion of new leaves, and severe infections can cause defoliation. Symptoms appear first in the lower branches of the tree. White oak and its relatives are more susceptible to this disease than red oak, and symptoms may be much more severe on white oak. Like ash anthracnose, homeowners can help their trees by reducing stress on the tree throughout the season. This will help the tree recover from the infection.

Oak anthracnose is commonly mistaken for Oak wilt, a more serious disease. To learn more about oak anthracnose visit http://www.extension.umn.edu/yardandgardenYGLNews//YGLN-June1504.html. To learn more about oak wilt in Minnesota visit http://www.extension.umn.edu/distribution/naturalresources/DD3174.html.

Venturia Leaf Blight in Aspen and Poplar
Several species of Venturia cause leaf and shoot blight in Aspen and Poplar. Infections start on young leaves and shoots as dark brown to black irregular spots. These lesions can expand very rapidly and kill the entire new shoot in the right environmental conditions. Infected shoots may be black and curled over in a shepherd's crook. Typically, early spring infections are limited to new tissue. The damage is not significant to trees over 10 ft tall. Infected tips can be pruned out so that they do not provide a source of new infection for the following season.

Leaf Curl of Cherry
This colorful disease is caused by the fungus Taphrina sp. Infection from this pathogen starts as thickened, crinkled or lumpy spots that turn from yellow to red. As the disease progresses leaf tissue darkens and dies. The fungal spores and mycelium can be seen as a white layer on the leaf surface. This fungus can move into the stem of the tree and cause swelling and formation of multiple branches from a very small area (a symptom called witches broom). Infected leaves will die back and fall off. The tree will replace them with healthy leaves. This disease can be pruned out by carefully cutting out infected branches several inches below visible signs of infection.

Oat Crown Rust on Buckthorn
Bright orange spots on both the upper and lower surfaces of the leaf characterize this fungal infection. Rust fungi do not kill plant tissue that they infect so this disease will not harm the buckthorn. It is, however, a good sign for vigilant homeowners and gardeners to go destroy the plant. Buckthorn is an invasive species that is very prolific in Minnesota. These plants crowd out native plants and in doing so reduce the availability of food and shelter for MN wildlife. Look for the bright orange infection on common buckthorn and remove these plants following the instructions in the following article: http://www.extension.umn.edu/info-u/environment/BD516.html

More information about buckthorn is available from the Minnesota Department of Natural Resources at http://www.dnr.state.mn.us/volunteer/julaug98/buckthorn.html.

Crane Flies
Jeffrey Hahn, Assist. Extension Entomologist

Typical crane fly Photo credit: Jeff Hahn

Tipula dorsimacula female Photo credit: Theodore Griggs

A common insect in Minnesota is the crane fly (family Tipulidae), a type of true fly belonging to the order Diptera. You can distinguish true flies from other insects because they possess two wings while other insects have four. There are more species of crane flies in North America than there are of any other group of true flies. Crane flies have very long, slender legs (which can easily break), a long elongate body, and long narrow wings. The wings can be clear or patterned. If you have really sharp eyes, you can detect a ‘V' - shaped suture on the thorax.

Crane flies range in size from 1/10th inch long to over two inches long. In Minnesota, many crane flies in Minnesota are about 1/2 inch long. Probably the largest crane fly in this state, Tipula (Nippotipula) abdominalis, measures in at 1 1/2 inches long. Most species are brown or black. The first reaction of many people when they see a crane fly is that it looks like a giant mosquito. Fortunately, crane flies can not bite and are harmless to people.

Watch for crane flies around any area that is moist, especially near lakes and ponds. However, there are other species that are found in meadows and other dry areas. Larvae are generally associated with aquatic or semi-aquatic habitats, ranging from moving water, areas covered with moss or algae, damp, rotting wood, or soil adjacent to streams. There are some species that are associated with drier areas, e.g. lawns or grasslands. Most crane fly larvae feed on decaying plant matter although some are predaceous. Crane flies are generally active at night and are easily attracted to lights. During the day, you can find them resting in shady areas on foliage or the sides of buildings.

An interesting crane fly species was encountered in early May. A high school student from Minnetonka, Theodore Griggs, observed two crane flies in his yard crawling around on the ground. They would periodically insert their abdomens into the ground as if they were laying eggs. He was curious what kind of insect there were. They were easily identified as a crane fly but it brought up an interesting question as to what species it was because of their behavior of ovipositing into the lawn which is not a common biology.

There are not any familiar native species that were thought to develop in grassy areas in Minnesota. However, there are two invasive crane fly species that are pests in turf, the European crane fly, Tipula paludosa and a closely related species, T. oleracea. Neither occurs in Minnesota so it would be important to determine if the observed insects were one of these pest species. Currently the European crane fly and Tipula. oleracea are primarily established in Oregon and Washington, although you can also find the European crane fly in Ontario, Quebec, and New York while Tipula oleracea has also been discovered in Michigan, New York, and Quebec.

After discussing this situation with Val Cervenka at the Minnesota Dept. of Agriculture, she contacted a colleague at the Washington Dept. of Agriculture. He identified the crane fly as Tipula dorsimacula (no common name), a native species. It is identifiable by the orange colored abdomen and the black stripe running down its abdomen. This species was well represented in the University of Minnesota Insect Museum collection with about 70 specimens collected from around Minnesota.

Dr. Jon Gelhaus, an entomologist and a crane fly expert with the Academy of Natural Sciences in Philadelphia, was contacted for information about this species. He said this species is not uncommon across northern North America including Minnesota. He has found adults of this species in open, grassy areas, early in spring. Females use their pointed sclerotized ovipositors to lay eggs into the soil.

He believes that the larvae develop throughout the year, overwinter in that stage, then pupate in early spring, with adults emerging soon afterwards. There appears to be just one generation with just a single adult emergence period. There is little known about its biology and it is not clear whether the larvae feed on decaying plant material or grass roots. If it does feed on turf, it does not appear to be at a level that causes any noticeable injury.

Cutworms in Lawns
Jeffrey Hahn, Assist. Extension Entomologist

Bronzed cutworm

Cutworm damage in turf Photos: Dianna Gurndeen

There are three cutworm species that are occasionally found feeding in lawns, black, bronzed, and variegated cutworms. Bronzed cutworms in particular were identified recently infesting neighborhoods in Anoka county. You can recognize bronzed cutworms as they have brownish-bronze colored bodies with a metallic sheen and five whitish or yellowish stripes that run down the length of their bodies. Cutworms grow to be about 1 1/2 to 2 inches long.

Don't confuse cutworms with sod webworm. While sod webworm also infests lawns and make burrows at the crown of the plants, they only grow to be between 3/4 - 1 inch long. They are brownish to grayish with rows of black spots. None of the above cutworms would match that description. Sod webworm larvae are typically found in June and again in August.

Bronzed cutworm eggs hatch in spring. They construct subterranean burrows in the soil or in the thatch but do not line them with silk (sod webworm burrows are lined with silk). They feed at night and rest in their burrow during the day. When feeding, cutworms clip grass stems, resulting in generally circular areas of brown or thinning lawn. These damaged areas will be relatively small at first but will grow larger as the cutworms become bigger. The good news is that they only have a single generation per year so you only have to deal with them in the spring.

Treat cutworms in lawns as soon as you notice their damage. Larger cutworms are more difficult to manage. Ideally you want to discover the insects before too much damage has occurred and while they are still relatively small (less than one inch long). We are probably past the time for treating bronzed cutworms this spring. However, if you catch them in time, you can treat them with an insecticide such as deltamethrin (e.g. Bonide Delta Eight™ Lawn Insect Control) or bifenthrin (e.g. Ortho® Bug-B-Gon® MAX® Insect Killer For Lawns Granules)

Azalea Sawflies
Jeffrey Hahn, Assist. Extension Entomologist

Typical azalea sawfly damage

Azalea sawfly close-up Photos:  Jeff Hahn

Gardeners have encountered a defoliating insects in their azaleas this spring. Although they appear to be small green caterpillars, they are actually a type of sawfly. Sawflies are generally smaller than caterpillars, possess 6 - 10 sets of prolegs (false legs located on the abdomen) and develop into non-stinging wasps. Caterpillars have 2 - 5 pairs of prolegs and turn into moths and butterflies.

In Garden Insects of North America (2004), Whitney Cranshaw lists two species of sawflies collectively called azalea sawfly, Amauronematus azalae and Nematus lipvskyi. These two species are very similar in appearance and habits and are difficult to distinguish. They apparently are easier to identify as adults.

The larvae hatch sometime during May. They are green, smooth skinned, and very closely match the color of the azalea leaves. Although you can find several sawflies on a given leaf, they are not very gregarious compared to other sawflies They feed along the outer leaf margin until eventually only the midvein remains. Azalea sawflies will feed until sometime in June. There is only one generation of this sawfly each year.

Treatment of azalia sawflies will depend on early detection. If most larvae are 3/4 to one inch long, they have already eaten their fill. However if most of them are smaller and especially if chewing damage to the plants is not significant yet, is worthwhile to manage them. You have several options for dealing with these sawflies.

If you are dealing with a small number of sawflies, an easy solution is to handpick them. Just throw them into a bucket of soapy water to be sure they die. Look carefully for them as they blend in really well with the leaves. Watch for partially chewed leaves and droppings on the leaves to help signal their location.

If physical removal isn't practical, consider using an insecticide. If you wish to use something less toxic, try insecticidal soap. However, you need to hit the larvae directly with the spray to be effective. Also, there isn't any residual activity so you won't kill sawflies that walk onto treated leaves later. Another effective, low impact product is spinosad (e.g. Conserve).

If you prefer to apply a residual insecticide, there are a variety of garden insecticides available that would work against sawflies such as esfenvalerate, bifenthrin, permethrin, and carbaryl (Sevin). Products containing these active ingredients are commonly available.

Get the low down on this month's insect pests at Insects
http://www.extension.umn.edu/projects/yardandgarden/EntWeb/Ent.htm

Contributors: Nancy Rose Patrick Weicherding Bob Mugaas

"Bolting" lettuces.

Rhubarb blooms. Photos: Beth Jarvis

Fruit, Vegetables and Flowers
Deadhead tulips and daffodils if you haven't already. As the foliage dies back, you can dig and lift any bulbs you want to replant in a different location.

Weed, weed, weed. Mulch flower and vegetable gardens to smother emerging weeds.

Water as needed. Spray for plum curculio moth and coddling moth on apples. Even if you missed the first spray, the second spray, 7-10 days after petal fall, is the more important. Home Fruit Spray Guide is at: http://www.extension.umn.edu/distribution/horticulture/DG0675.html

Those blobs of foam/bubbly spit you see on flowers and weeds are spittle bugs. Ignore them. http://www.extension.umn.edu/yardandgarden/YGLNews/YGLN-June1500.html#spittle

Rose slug sawfly is defoliating roses left and right. http://www.extension.umn.edu/distribution/horticulture/components/DG6703fig13.html and http://www.extension.umn.edu/distribution/horticulture/DG6703.html#13

Fourlined plant bugs should be active soon if they're not already. http://www.extension.umn.edu/yardandgarden/YGLNews/YGLN-June0199.html#bug

Container plantings should be checked at least twice a day and watered as needed as they dry out quickly on hot, dry days.

Tomatos and peppers can be planted now. If you plan to cage them, do it as you plant them. Add cutworm collars as you plant. Juice cans, toilet paper rolls, or even strips of aluminum foil paper crimped around the stems will thwart cutworms.

All warm season vegetables can be direct-seeded now. That includes beans, zucchini and other squash, cucumbers and basil. Plant sweet corn in (at least) 2 row blocks. To keep neighborhood squirrels and raccoons well-fed, plant new blocks every two weeks or so to prolong the season.

Leaf lettuce can still be planted in a cooler, shady spot and kept well watered. Head lettuce (and cabbage) have compressed stems, as the leaves are stacked right above each other. In response to changes in daylength and temperature, lettuce will "bolt" with the stems, the internodes elongating, as the plants attempt to bloom and set seed.

If your rhubarb is blooming, remove the flower stalks. You may harvest rhubarb until July 1 or so.

Lawns:
Crabgrass is germinating and in some places it's at the 2-3 leaf stage, pretty much normal for this time of year. It can germinate from the 20th of May on. If pre-emergence was applied in mid-April, you may benefit from a second application right now. If germination has started, lawn owner can use Dimension, trithiopyr, on it. Dimension only works on young seedlings, once crabgrass is past a couple true leaves, Dimension isn't effective. Iit's generally available mixed in a weed and feed fertilizer, and fertilizer may have already been applied. Commercial applicators can get it as a stand-alone product. Team is available as a second application, stand alone product and is an alternative for lawn owners. All pre-emergence products should be watered in wiuth 1/4-1/2" of water to get it onto the soil surface. Drive, available to commercial applicators, will work. "Younger is better" for treating crabgrass after it's germinated.

If you've not had adequate rain recently, it wouldn't hurt to water. Adequate is about an inch of rain a week.

Maintain higher mowing heights of 2.5-3" to enable grass to maintain a deeper root system. Deeper is relative to time of year as summer grass roots of our typical cool season lawn grasses are more shallow than in spring or fall.

It's too late to core aerate or dethatch home laws until fall. They need weeks of cooler weather to repair damaged roots.

Lawns going to seed is a function of daylength. Cool season grasses, such as those found in home lawns, will bloom and set seed in response to daylenth. They flower naturally at at various heights, depending at height mowed. Grass seed takes months to ripen so you will not effectively "reseed" your lawn by "letting it go to seed" this spring.

Trees and shrubs:
Now is a good time to prune the new candle growth on pines and spruce. Do not prune back into the older growth. It's a good time to prune spring flowering shrubs such as lilacs, forsythia, and bridal wreath spirea.

Start scouting for insects and diseases. June is the month for sawflies--those green caterpillars that feed heavily on evergreen needles.

Report gypsy moths to the Minnesota Department of Agriculture “Arrest the Pest” Hotline at: 651-201-MOTH (6684) or 1-888-545-MOTH (6684). Read about invasives at: http://www.mda.state.mn.us/invasives/default.htm. Anthracnose is common given the amount of spring rain and cool moist weather. Maple and ash that drop green leaves, starting from the bottom up possibly have anthracnose. Oak anthracnose often causes tan-clored blothches and leaf distortions on the fallen leaves; it is often confused with early symptoms of oak wilt. Oak wilt genrally starts from the top down and anthracnose starts fropm the bottom up. See Michelle's article on these above.

Keep all newly planted trees watered--those planted in at least the last 2 years. If you've mulched around newly planted trees, be sure the mulch is 2" away from the bark as the bark of young trees can rot out due to the close proximity of the mulch.

Editorial Notes

'Globemaster' allium Photo credit: Beth Jarvis

Several readers e-mailed to inquire where the table was in the hydrangea article in the last issue. I missed it. I've added it to the article in the archives. Go to: http://www.extension.umn.edu/yardandgarden/YGLNews/YGLNews-May1506.html#hydrangea I was out of the office immediately after for 2 weeks.

Dave Bedford, fruit breeder, has agreed to visit with me some rainy day to talk about small fruits for home yards/landscapes.

Dave Hanson, forester and the guiding light for the Shade Tree Advisor course, will be writing an article some time this summer on growing evergreens in shade. I've asked him to touch on the physiological drawbacks to shade vis a vis incidence of winter injury, among other things.

Please feel free to cut and paste any of the articles for use in your own newsletters. All we ask is that you give our authors credit.

Back issues Yard & Garden Line News are on the Yard & Garden Line home page at www.extension.umn.edu/yardandgarden/.

Deb Brown answers gardening questions on Minnesota Public Radio's (MPR) "Midmorning" program on the first Friday of every month at 10 a.m. The program is broadcast on KNOW 91.1 FM, and available state-wide on the MPR news radio stations. (Scroll down for map.)

For plant and insect questions, visit http://www.extension.umn.edu/askmg. Thousands of questions have been answered, so try the search option in the black bar at the top left of the board for the fastest answer.

If you would like to receive an e-mail reminder when the next issue of the Yard & Garden Line News is posted to the web, just send an e-mail to: listserv@lists.umn.edu (note: the second E in listserve is omitted), leave the subject line blank, then in the body of the message, type: sub yglnewslist or to unsubscribe, enter: unsub yglnewslist

Happy gardening!

Beth Jarvis
Yard & Garden Line Project Coordinator


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