Yard & Garden Line News
Volume 6 Number 6                                                               May 1, 2004
Features this issue:
 Why? Oh, Why Do We Prune Trees?
Sudden Oak Death
Time to Hit the Garden Centers
Root Maggots
Early May Garden Tips
Editorial Notes


Why? Oh, Why Do We Prune Trees?
Dave Hanson, Research Specialist, Urban and Community Forestry

Bur Oak: Pruning to correct bad decisions. Photo credit:
Dave Hanson
Many of us have had the pleasant (?) experience of the tag-along-toddler with only one question on their little mind, "Why?" This repeated inquiry can be, shall we be polite and say, challenging! We understand that the tag-along-toddler is learning and cataloging some tidbits for later. Whether people are listening to a speaker or reading an article - the topic of pruning reduces many of us to the tag-along-toddler phase of our lives with one burning question "why?" This article will repeatedly ask that question and hopefully provide some answers besides, "because!"

Let's get started with this comment: Trees in a "natural" forest are seldom pruned and they do fine. On the other hand people in urban areas insist on pruning trees frequently…

Why?
Are urbanites simply "control freaks" with a need to control some living thing? Not exactly, there are valid reasons (safety, health of the tree, and aesthetics) to get out there and take a good look at the structure and condition of the trees in our landscape. Trees in the natural forest for example tend to randomly drop limbs (natural pruning) and fall over unpredictably during storm events or from internal decay.

Increased potential for property damage and personal injury in the urban forest dictates that limbs dropping and trees falling over should be predicted and controlled, as much as possible. Any tree may develop structural problems or become damaged in such a way that it presents a risk. So, developing a regular inspection and pruning cycle for landscape trees is highly recommended to help eliminate some of the "risk."

Many consulting arborists are trained to identify those "risks" in trees and can make recommendations to eliminate or reduce the risk to an acceptable level. Often reducing the risk can be accomplished without removing the tree by utilizing one of the following approaches.

Three basic approaches to pruning:
Crown reduction for power line clearance Photo credit:
Chad Giblin
From the United States Forest Service brochure "How To Prune Trees" (Bedker et al.):

1) Crown reduction:
A method to reduce the overall height of a tree.

Why?
Most often put into practice under power lines to alleviate line conflicts. According to a flyer from Connexus energy (Spring 2004) - "Trees are the number one cause of power outages."
This approach may also be employed to clear site lines for a scenic overlook or vista.

Crown reduction or drop-crotch pruning is not topping; yet, it should be considered as a last resort treatment.

Why?
Crown reduction opens multiple large and small wounds on a tree and those wounds can be entry points for insects or disease.

2) Crown thinning / cleaning:
This technique is often used to open up the canopy for air movement through the tree and to provide light penetration to the understory. Beyond that, this pruning approach considers many things--correction of structural problems such as tight branch angles, included bark, crossing branches, broken or split tree parts.

Why?
Correcting structural problems can prevent problems from loading events (wind, ice, or snow) or simply the weight of a maturing limb. Consider a limb or branch to be a lever arm that you learned about in physics - if you load that lever arm and it is not firmly attached to the tree or was previously damaged it is likely to fail.
Co-dominant stem
split out under a
snow load. Predictable and preventable. Photo credit:
Josh Plunkett
Crown cleaning also consists of removing deadwood, hangers (broken branches) as well as removal of diseased wood or insect infestations.

Why?
Deadwood and hangers (lodged, detached branches) present a risk to people, cars, houses and other objects (targets) below. Also, by removing signs of disease and / or insect infestations a serious problem for the tree may be stopped before it progresses to a full blown disorder.

Maintenance and correction of storm damage fall into this category.

3) Crown raising:
Simply put, this is the removal of lower branches to improve site lines near roads and to allow for movement of people and equipment under trees. Along city streets for example, many municipalities remove permanent tree branches to a minimum height of 16 feet from the ground or street surface.

Why?
Garbage trucks and other big rigs will prune the limbs by tearing them from the tree often causing irreparable damage to the main stem.

This ruptured stem was caused by a delivery truck hitting the low hanging branch on the right. Photos: Dave Hanson
Along sidewalks, permanent tree branches should be a minimum of 8 feet above the sidewalk to allow for pedestrian traffic and snow removal equipment.

Depending where a tree is located in the landscape determines if branches are raised or allowed to sweep to the ground.

Why?
Low hanging tree branches restrict movement and present poking and head-banging hazards in our yards and parks. So, in some instances the tree branches should be raised to allow people and equipment to move underneath

Putting this into Practice:
What or who is an arborist?
For more information visit:
www.isa-msa.org
So, with those approaches outlined here's a prediction - If you are responsible for a landscape that contains trees - there is some pruning in your future…or there should be!

But hold on, before you grab the chainsaw, consider taking a brief course on pruning or at least read some of the current research on pruning trees. Unfortunately, there are still a lot of incorrect pruning practices taking place - bad pruning cuts, pruning practices that permanently damage trees and pruning performed during the wrong season for the tree.

Flush cutting:
There is a three cut method to pruning: cut number 1 is an undercut of the branch to prevent the bark and wood fibers tearing down the main stem. Cut number 2 simply removes the weight of the branch outside of cut number 1. The third and final cut removes the branch stub near, but outside of the branch collar. However, a person can still find literature that describes the final pruning cut as follows:
"Then cut the remaining stub flush and parallel to the main trunk"
That is an exact quote from a currently available publication copyrighted in 1980. That description of the final cut is completely wrong!

Left: Branch Collar - note the swelling of branch material Right: Left is the proper cut at the branch collar. Right is the incorrect large flush cut. Photos: Gary Johnson
Why?
The final pruning cut should take into consideration the branch bark ridge and the branch collar. Simplistically, the branch collar is a zone of fast growth and within this zone there are several protection mechanisms that protect the trunk of the tree from decay organisms that may enter the branch. By leaving the branch collar intact - the main trunk of the tree will be better protected from decay processes.
A pruning cut that is "flush and parallel to the main trunk" leaves a large oval wound in the trunk tissue that a tree will have a difficult time sealing over with callus material. Protection zones and mechanisms are compromised and the tree is more likely to decay.

Topping and Tipping:
There are still companies topping trees and tipping branches on trees. There are still homeowners requesting that trees be topped and that branches be tipped. Both topping and tipping are harmful practices to trees.
Tree was topped to improve view of store  signs Photo credit:
Patrick
Weicherding:

Why?
Topping and tipping are pruning cuts made indiscriminately on limbs with no regard for placing the cuts near protection zones. These cuts almost always result in rapid decay of the remaining portion of the limb, while at the same time stimulating large amounts of new growth in the form of epicormic branches also known as water sprouts. The new growth is typically poorly attached and begins to add considerable weight to a limb or branch being weakened by decay.

When to Prune: How about the perennial question, when is the "best" time to prune a tree? Let's turn that question around - when is the "worst" time to prune a tree? From the trees point of view the months of April, May and into June may be the worst time to prune.

Why?
First, this is the time of year when trees deplete their energy reserves and put most of it into new leaves. Pruning at this time places the energy that has been moved into branches, twigs and leaves onto the burn pile or into a landfill. This practice places the tree in a stressed state, with an energy deficit that may not be completely recovered in that season.

Secondly, this is an active time of year for many disease and fungal pathogens (Oak wilt for example). The warm spring months of April, May, and June typically bring high humidity from spring rains, these factors provide an ideal environment for many pathogens to flourish. So, you have the environment for a pathogen, you have a pathogen - now, to complete the "disease triangle" there has to be a host! How about that tree in your front yard that was just pruned, it is probably a good host for some pathogen. So, yes, spring can be a bad time to prune.

Another "bad" time to prune is late autumn into early winter.

Why?
Pruning in late autumn and early winter can lead to winter injury. The pruning wounds may not have time to "harden off" or prepare for winter. This can lead to deeper freezing in the tissues around the wound and in essence a larger wound can be created that the tree will have difficulty dealing with.

So that leaves us with the summer months and late winter (dormant season pruning). Typically late winter or dormant season pruning is the "best"" time to prune.

Why?
During the late winter months (February and March), harmful pathogens are at a minimum, mostly inactive; therefore, this is a safe pruning environment from that standpoint. During this season, deciduous trees have hardened off and when the growing season begins the wounds will be sealed and the callusing process will begin.

When to Hire a Pro:
This brings us to another big question, should a homeowner hire a professional arborist to do the tree work or get out there and do it by themselves?

Remember, the balance of a tree or a tree limb can be difficult to judge. While the task at hand may appear simple, tree work is a very dangerous profession.

An Absolute Rule:
If there is a power line nearby - consult with an arborist.

Why?
Power lines and in-experienced, untrained workers do not mix!
At a minimum call the power company to discuss options. You may be able to schedule a line drop for a few hours. It is easier to physically disconnect and drop the line than to replace connections and repair damage after the tree falls the wrong way…assuming, you survive the incident and are able to repair the damage.

Some Basic Guidelines:
If the job requires a ladder, a consultation with an arborist may be in order.

Why?
By working from a ladder with a hand saw, chainsaw or even a pole pruner much of the necessary pruning cannot be accomplished and often the tree will end up be "lion's tailed." Lion's-tailing leaves a tree with a reduced canopy, thus reducing its ability to photosynthesize. Arborists on the other hand will enter the tree with climbing gear (rope and saddle - NOT SPIKES) and or use a boom truck with a bucket to reach the tree top and branch ends.

Pruning Disaster: Power lines, inexperience, a ladder and a chainsaw. Photo credit:
Dave Hanson
If you think the job requires a chainsaw, consulting an arborist is recommended.

Why?
Chainsaws are tools for trained, experienced hands. Untrained operators often do more harm than good to both the tree and the operator. Most of the pruning that a tree needs can and should be accomplished with a "hand" pruner or pruning saw.

Exception: Yes, commercial /municipal arborists and tree-workers are trained in the use of chainsaws and will use chainsaws to complete a portion of their work. However, note that they also carry handsaws and use them appropriately.

If you have storm damaged trees, consult an arborist, A damaged tree may be able to stay in the landscape, safely for years to come.

Why?
Arborists are trained to understand the structure of a tree and to understand how a damaged tree will respond to treatment and more importantly and arborist can answer the question - "Can this tree safely remain in the landscape?"

If you are planning a landscape, please consult an arborist or a landscape designer.

Why
It is important to select the right trees for your locations. Putting the right trees in the right places can dramatically reduce the costs of pruning and maintenance in your landscape.

The bottom line is that feeling the need to prune trees does not make urbanites "control freaks"; rather, living in geographically condensed spaces in close proximity to mature trees renders us and our belongings potential targets to falling tree parts. Thus, out of necessity we need to care for our trees not only so that they are pleasing to look at, but so that they remain healthy, safe features in our landscape.

Why?
Because!

Work Cited:
Bedker, Peter J., O'Brien, Joseph G., Mielke, Manfred E., How To Prune Trees. United States Department of Agriculture, Forest Service Publication
http://www.fs.fed.us/r6/uma/nr/silv/How%20To%20Prune%20Trees.pdf

Sudden Oak Death
Janna Beckerman, Extension Plant Pathologist

The name says it all: Sudden Oak Death (SOD). In addition to certain species of oak, it infects and kills a variety of other trees and ornamental plants. Currently, over 50 hosts have been identified, and more are added each month.

Most importantly, it's not coming to a plant near you--At least, not yet. And hopefully, with new quarantines and restrictions in place, it won't be arriving any time soon. April 9th, the United States Department of Agriculture issued an order restricting the movement of nursery stock from California nurseries.

What is SOD?

Sudden oak death, as the name suggests, is a disease that is capable of rapidly killing certain species of oaks. It was first identified in California, in 1995. Two years earlier it was identified in Germany and the Netherlands, killing rhododendron. Because the pathogen originally infected and killed tanoaks, an undesirable, understory scrub tree, it generated little interest. As other species of oaks began dying, including coast live oaks, California black oaks, Shreve oaks and canyon live oaks, people began to take notice. However, by this point, the disease was well established and eradication no longer an option.

What are the symptoms of SOD?
To understand this disease, it is important to recognize that there are two categories of hosts: bark canker hosts and foliar hosts. The bark canker hosts are oaks of the red oak (section Lobatae) group, coastal redwood and Douglas-fir. Hosts that become infected on the trunks develop cankers that often leading to death. Symptoms are bleeding or oozing of a reddish-brown sap on the lower portion of tree trunks. Foliar hosts include rhododendrons, bigleaf maple, and many others that become infected on the leaves and small branches. These infections rarely cause death, and symptoms include lesions that mimic sunscald, twig canker, and dieback. Although symptoms from these infections are not severe, and are rarely fatal, the infections produce enormous numbers of spores that can infect neighboring, susceptible oaks (1).

What is unusual about this disease is the severity of disease symptoms coupled with the broad host range of the pathogen. To date, this disease has killed oaks in California and one county in Oregon. However, Northern red oak and pin oak have been tested in laboratories at the University of California at Davis and both are susceptible to the disease as seedlings. Furthermore, a mature Northern red oak in the Netherlands has recently shown symptoms of this deadly disease, suggesting that what happened to the seedling will also occur in mature specimens. No species in the white oak group (section Quercus) have been found with the disease in the field in California, Oregon, or Europe. It is not known how many of America's approximately 100 species of oak trees and hybrids, or other species of plants, would be vulnerable to sudden oak death. Recent counts have found more than 12 plant families, from poison oak in the Anacardiaceae family to coastal redwood in the Taxodiaceae are susceptible (1).

What causes SOD?
The pathogen that causes SOD is Phytophthora ramorum (pronounced Fi-toff-thor-a ra-mor-um). This pathogen belongs to a group of organisms in the Kingdom Chromista, and has characteristics similar to fungi, plants and animals. It spreads throughout the plant by hyphal threads (like fungi), produces spores (like fungi) that have flagella and swim through water (like animals), but its cell wall is made up of cellulose (like plants). Because P. ramorum is not a fungus, most fungicides labeled for control of other fungal diseases are not effective against it. Unscrupulous people have already tried charging to spray their trees and lawns in Florida to protect against SOD.

How does it spread?
P. ramorum may be spread through infected wood, soil and rainwater. The fact this organism has a free swimming stage is important to its spread. Spores are spread through the air under moist and windy conditions. However, the most important way this pathogen spreads is through the movement of infected plants and plant parts. This is where the threat lies for Minnesota plants.

In the past two months, P. ramorum has been positively identified in 61 plant nurseries in nine states. If the pathogen could become established in areas where environmental conditions are cool and damp enough for it to establish, sudden oak death could change the structure of American forests and landscapes, just as Dutch elm disease did 50 years ago, or the chestnut blight did 100 years ago. To develop a better understanding of the nationwide scope of the disease, the USDA is continuing to survey nurseries in all 50 states for the disease, and the U.S. Forest Service is surveying forests in 34 states.

What can we do?
At this point, you should be aware that this is a new disease problem, with the potential of spreading throughout the United States. The tremendous spread of this pathogen in the past two months demonstrates how easily it can spread across the country. No one can predict what the consequences could be if it gets introduced and becomes established in Minnesota. For this reason, it is important to try and prevent it from getting here, and know how to identify it so it can be quickly eradicated.

Bibliography: 1. Davidson, J. M et al. 2003. Sudden Oak Death and Associated Diseases Caused by Phytophthora ramorum. http://www.plantmanagementnetwork.org/php/shared/sod/

For more information on SOD, go to:
North Central Pest Management Center
http://www.ncpmc.org/NewsAlerts/index.html

Practical information on Sudden Oak Death in California
http://cemarin.ucdavis.edu/index2.html

Sudden Oak Death and the California Oak Mortality Task Force
http://www.suddenoakdeath.org/

Please check out the new diagnostics web pages at
http://www.extension.umn.edu/projects/yardandgarden/diagnostics/


Time to Hit the Garden Centers
Deborah Brown, Extension Horticulturist

Leaf lettuce-- among many veggies direct- seeded in the garden. Photo credit Deb Brown
This is one of those times most gardeners anticipate with glee: time to hit the garden centers. Luckily there's no end of wonderful nurseries and garden centers throughout Minnesota. They range from small rural greenhouses that specialize in bedding plants and brightly colored hanging baskets for city folks heading out to the cabin, to larger, full-service operations, active year-round.

Many people prefer the one-stop shopping aspect of visiting a garden center that has a comprehensive line of merchandise to accompany its plants and seeds. But there are also smaller garden centers that frequently offer a good selection of plants along with personalized service such as creating container gardens on the spot, from plants you choose. And then there are specialty nurseries that may concentrate on unusual perennials, native prairie plants, shade-lovers, or some other interesting category of plants.

Shopping's more fun when it's not too crowded. But there are times when you just can't avoid a crowd at the garden center – especially on sunny, warm spring weekends when Minnesotans experience the collective urge to plant. But it's so much easier to shop when the aisles aren't mobbed.

If you're only free on weekends, your best strategy is to try going first thing in the morning – really early – when the nursery or garden center first opens its doors. Not only will there be fewer shoppers, but shelves are generally re-stocked at night, so you'll have a full selection of plant from which to choose. Another strategy would be to shop on a cloudy or rainy day. You may not like the weather, but you'll have the garden center practically to yourself! Take your plants home, keep them in a shady, protected site, then do your planting a day or two later, once your garden soil is dry enough to work in.

'Bright Lights' cosmos are direct-seeded in mid-May. Photo credit: Deb Brown
If you're able to shop for plants on a week day, by all means take advantage of those hours when many other people are busy at their jobs. Tuesday, Wednesdays, and Thursdays are usually slowest days. Mornings are often slower than afternoons. Garden centers typically run their weekend specials from Thursday through Sunday, so shopping on a Thursday may give you the "weekend price advantage" without the weekend crowds of fellow shoppers.

Plan ahead for what you need. It's always good to be organized and have some sort of plan in mind or better yet, written down, when you visit a well-stocked garden center. Otherwise it's easy to feel overwhelmed and want to buy everything you see. You can easily end up with too much or perhaps with the wrong plants for specific locations. It's sort of like going to the grocery store when you're really famished. And after another long winter, we're all famished for planting season to begin!

Keep your garden color scheme in mind when you look at flowering annuals and perennials. Think, too, about the height and potential spread of the plants you buy. Most important, though, consider their light requirements carefully. When you pick plants that are well-suited to the environment in your yard, they're often capable of putting on lots of growth over our four to five month growing season. At the same time, poor choices not only will bloom sparsely, they'll grow less vigorously and be more vulnerable to disease and insect problems.

If some of your flowers or vegetables were beset with insect pests or were badly diseased, think long and hard about the wisdom of trying those particular plants again. Often there are good substitutes – surely among the many flowers we can grow here – that will allow you to garden with minimal use of pesticides.

Choose large, well-developed plants for containers. Photo credit Deb Brown
Bigger is not necessarily better. When it comes to flowering annuals, large, well-developed plants are probably not your best buy, unless you're goal is creating an "instant garden." Choose those big individual plants for window boxes and garden tubs where you want lots of color, right from day one. For most purposes, however, smaller bedding plants will do just fine. They'll transplant easily and grow rapidly, often catching up with larger counterparts before many weeks have passed.

Look for bedding plants growing in divided "cell packs." It's easier to remove them for transplanting without damaging their roots. Plants in packs without dividers have long, spread out roots, making it more difficult to ensure each has an adequate supply of roots when you divide them. In that case, your best bet is to use a sharp knife to cut the soil into cubes for planting, rather than trying to pull the plants apart.

As for perennials, the larger the plant, the sooner it will function from a design standpoint in your garden. On the other hand, buying younger, smaller plants can really help stretch your gardening budget. The trade-off is that they may not bloom this year, and it will take longer for them to attain their full size and stature.

Don't forget to pick up some seed packets. Most vegetables and many wonderful flowering annuals may be direct-seeded into the garden, once the soil warms this month. You can even start flowering perennials outdoors in a "nursery bed," then transplant them next year when they're larger.

Root Maggots
Jeff Hahn, Assistant Extension Entomologist

Root maggot. Photo credit:
Entomology Dept.
There are two species of fly maggots that can be pests in gardens, cabbage maggot and onion maggot. Cabbage maggots attacks crucifers, including broccoli, radishes, cabbage, cauliflower, and turnips, while onion maggots infest onions. Root maggots can occur any year but are more common during cool, wet springs.

Root maggots spend the winter as pupae in the soil. They emerge in spring as adult flies. These flies are dark gray, have stripes on their thorax and resemble small house flies. The females lay eggs at the base of plants and in nearby cracks in the soil. The eggs hatch within a week into small, legless, whitish maggots. These maggots move into the soil and feed on the roots of crucifers or onions for about four weeks. Infested plants can appear discolored, wilted, or stunted. Depending on the age of the plants and how many maggots are attacking them, damage can be severe enough to kill these vegetables.

You must be proactive to protect your vegetables. Once you find damaged plants, it's too late to treat them. In the past, you could apply diazinon granules into the soil as you were planting crucifers or onions. However, diazinon has been phased out and is no longer available to the general public. It was hoped that another insecticide would be available with labeling for soil treatment in home gardens but this has not happened. So currently there is no insecticide available as a preplant treatment for cabbage and onion maggots.

Without insecticides, your only real option is to use a floating row cover, or similar barrier, to protect your plants. Floating row covers are readily available through gardening catalogs and stores. This barrier should allow sunlight and rain in and should reach the ground. You should have the barrier set up in your garden by the time adults flies are laying eggs which is early to mid-May. Keep the barrier in place until the end of the month when the flies are finished laying eggs. Floating row covers may not be practical in large gardens.

You should base your need for a barrier on how much root maggot damage you've had in the past. If you have experienced problems on a regular basis, then assume you will see them again this year. If however, you have not encountered root maggots often in the past or not at all, you can assume you don't need to do anything this season.

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


Early May Garden Tips
Beth Jarvis, Yard & Garden Line

Compiled from conversations with David Hanson, Urban Forestry; Bob Mugaas and Bob Olson, Regional Extension Educators; and Jim Luby, Fruit Breeder

Tulips and grape hyacinths. Photo credit:
Beth Jarvis

Drought Update for May 1

Mark Seeley's crystal ball predicts a cooler and wetter first half of May. Seeley, Extension Climatologist, notes this will certainly help our gardens as most parts of Minnesota will be posting below average rainfall numbers for April. The only part of the state where April's showers were normal to above was in the Arrowhead--Pine, Carlton, north and eastward.

We're still running at a soil moisture deficite that started last July. If your tap water tastes a bit off, it's not a surprise. Watershed levels are down so off flavors aren't getting diluted.



(These recommendation are based on Twin Cities temperatures. Adjust for northern Minnesota..)

Fruit:
*Plant strawberry and any other catalog ordered fruit plants as soon as as your can.

*Prune out any 3 year old raspberry canes. Any canes that set fruit last summer can be pruned out down to the ground. Burn or trash the canes. They don't compost well and may harbor disease.

*Weed fruit beds.

*Renew mulch around fruit trees.

*Water any plants that have not received an inch of rain this week. Make up the difference w/the hose.

*Spray any apples or crab apples for apple scab or cedar apple rust as timing permits according to the Home Fruit Spray Guide.

*Not sure if you had apple scab last year? Read about it here:
http://www.extension.umn.edu/yardandgarden/YGLNews/YGLN-July0103.html#scab

Lawn:
*If you haven't reseeded dead patches, finish the task now. You're about out of time for this spring.

*If you've reseeded and have concerns about crabgrass, Tupersan will allow coolseason grasses to grow.

*Phenology for applying pre-emergence herbicide (generally): when lilac flowers show color, forsythia blooms drop, and flowering crabapple flowers just begin showing color.

*Now's a fine time to apply pre-emergency in warm, sandy soils, south or southwest slopes. Cooler, shaded, clay sites can wait a bit.

*Regardless of whether you use liquid or granular, or corn gluten meal, water your pre-emergency herbicides in well using 1/4-1/2" of water.

*Lawn grasses' shoot extension rate is greatest now because of flower production. Cut your lawn long, 2 1/2-3" because the longer blades prompt more root mass development (greater drought proofing) and actually slows some weed seed germination. Weed seeds often wait for light signals to prompt germination. If they're kept in the dark, they won't germinate.

*If we stay dry, be sure to water your lawns. The grass is experiencing a flush of growth. That lush growth is stockpiling the carbohydrate supply the lawn will need to get through summer dormancy.

*Generally, by the time you mow a newly seeded area, you can use standard pre-emergence herbicides.

*Broadleaf weed control can be started as soon as air temperatures are consistently 60 degrees.

*Weeds won't die from herbicide if they're under drought-stress/dormant. Water them, then kill them.

Trees/shrubs:
*Avoid pruning trees while leaves are forming and expanding as the trees are putting energy into leaf and wood production.

You can resume pruning in late June-early July.

*Don't prune oaks until July.

*Don't prune honeylocust until August or September to reduce threat of nectria canker.

*Water, water, water.

Flowers and Vegetables:
*Water your plants when rains aren't sufficient.

*Fertilize spring blooming bulbs while the foliage is still green and growing.

*Wait to plant any store bought bedding plants until the weather's stabilized. They need to be acclimated to being outside so gradually increasing exposure outside is best, Do it gradually over roughly 2 weeks.

*Seedlings you've started need to go outside to harden off, too.

*As your tulips and daffs finish blooming, snip the faded flowers off with scissors. Leave all the foliage alone until it dies back on its own. Don't braid or bunch up daffodil leaves. They need to grow to recharge the bulb for next year.

*Get your soil tested. A routine test should be done annually. It takes 7-10 days to get the results and costs $15. You needed do other testing unless the site has a history of nutrient related problems.
http://soiltest.coafes.umn.edu/

*Peppers, tomatoes and eggplant should be kept inside (warm) until mid-May. Then harden off in sunny, warm site. Peppers should go into the garden when the soil and air have completely warmed as they will be stunted if they get chilled.

Wildlife:

*If you've been bothered by bunnies:
http://www.extension.umn.edu/projects/yardandgarden/AAMG/wildlife/rabbits.html

*Trails in grass are probably voles. For guidance, see:http://www.extension.umn.edu/projects/yardandgarden/AAMG/wildlife/voles.html

Editorial Notes

Bloodroot--a spring ephemeral. Photo credit:
Beth Jarvis
Next issue, Mark Seeley will discuss what happened to a new proposed USDA zone map (and the myth of the TC being zone 5) and other issues. In June, Patrick Weicherding will discuss what, if anything, needs to be done with holes in trees and similar wounds. Such oles were once filled with everything from concrete to polyurethane foam. Technology has changed as we've learned that filling is damaging to the tree. So what's a tree owner to do with that big hole in a tree?

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/.

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.

Deb Brown answers gardening questions on Minnesota Public Radio's (MPR) "Midmorning" program on the first Thursday 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.

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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