2. Control Noxious Weeds This Spring
By John Wilson, UNL Extension Educator
Fall is the best time to control most noxious weeds, but we should not neglect our opportunities this spring. Besides, many weeds require consecutive treatments in fall and spring to get them to manageable levels. Here are some tips to help you get on top of these weeds before you get one of those dreaded letters from the weed control superintendent or FSA office. (They have no sense of humor!)
I will touch on each of our three major noxious weeds. The timing of control I mention on each of these might vary a week or more, earlier or later, depending on the weather and your location. Early spring, move up the control time... later spring, move it back. I will go in the normal order we would control these weeds in the spring, earliest to latest, which also happens to be from the easiest to the most difficult to control.
Clicking on a weed name will take you to a UNL Extension publication that will give you more information about identification and management of these weeds.
Musk Thistle: This noxious weed is the easiest to control in the spring... but we can't wait too long! Musk thistles formed a rosette, much like a big dandelion, last summer and fall. It continues to grow in this form this spring. Around the first of May it bolts (sends up a flower stalk) and is much more difficult to control.
When we have good growing conditions, adequate soil moisture and warm days, musk thistle rosettes are fairly easy to control with several different herbicides. Once they bolt, many of these herbicides will not give adequate control and the ones that will give some control are more expensive.
If they've started to flower, a hoe or shovel is probably your best method of control, but it is important to clip those flowers to prevent them from going to seed. If you cut off a plant and can see the distinct purple color in the flower, even if it isn't fully open, some seeds will mature on the dead plant and perpetuate your battle with this weed.
Leafy spurge: Our normal timing of spring control would be in mid-May when the spurge buds or starts to bloom. It has a distinct yellow "flower" (actually what we see is a modified leaf, but it looks like a flower) on an upright stem. It is easy to confuse some of our wild mustards with leafy spurge. The easiest way to distinguish between the two is to break the stem or leaves. Leafy spurge will have a milky sap (like a milkweed) while mustards do not have this kind of sap.
In spring, you should treat leafy spurge just as the tops start to turn yellow. This weed generally grows in patches and you should spray 20 to 30 feet beyond any plants that you see to get those coming up from the roots. This perennial weed has an extensive root system and you may need to come back a couple of weeks after your initial application to treat the weeds that escaped. Then be ready to retreat the area in the fall for new plants or escapes.
Canada Thistle: This perennial problem weed would be the last one we would normally control in the spring. Unlike other thistles, we want to wait until flower buds form which typically occurs in mid- to late June. Getting good coverage with our sprayer is the biggest challenge because grass may be as tall or taller than the thistles. As with leafy spurge, Canada thistle is usually found in dense patches and it is important to spray beyond the edges of the patches.
Even though it is earlier than we normally recommend, I can tell you from personal experience that you can get good control earlier in the spring if the Canada thistle are in CRP. I burned off my grass in April and then sprayed the thistles once they greened up in mid-May. This is about a month earlier than we normally would treat them, but I think I got just as good control with better coverage before the grass got tall. I still needed to go back and spot treat those that I missed later in the summer.
There are two important things to remember when trying to control these noxious weeds...
1. Fall is the best time to control them when the plants are sending nutrients to the roots for growth the following spring. Treatments then will move the herbicides to the roots and give us better control.
However, if we have these weeds in spring, that means we missed controlling them last fall or we didn't get complete control. We need to treat them now rather than waiting until fall. Then we should come back in the fall and control the ones we missed or that came up from seed over the summer.
2. None of these weeds can be completely controlled with a single application of any herbicide. One of the reasons they are classified as "noxious weeds" is because of the difficulty of control. Even if we control all the top growth of any of these weeds, there will likely be some that come up from seeds or roots.
Again from personal experience, I've dealt with all three of these weeds on my place. By keeping after them each year, I've reduced the area they infest from over 100 acres to less than a couple acres... but you can be sure I'll be out there with my backpack sprayer this spring treating those little patches that keep coming back. The good thing is, they keep getting smaller each year!
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3. Handle Chemicals Safely
By Sharry Nielsen, UNL Extension Educator
Chemicals are useful for many of the tasks done every day on farms, acreages and at home. Pesticides, like garden dusts, are used to kill bugs in gardens, fields, and homes. Herbicides kill weeds in gardens, lawns and fields. Fertilizers help plants and grasses grow. Fuel is a chemical used to power vehicles and machinery. Disinfectants and cleaning supplies keep our homes clean and free from harmful bacteria.
Few would want to get rid of the chemicals that make our lives easier and safer, but we do need to handle them with care. Unless you are willing to learn how to safely handle chemicals and to use recommended precautions, you should leave their use to professionals.
Farm and home chemicals can enter the body through the skin, orally (by eating), or by inhaling. The smaller the body, the less chemical it takes to make a person sick. Some chemicals, which might make an adult ill, are fatal to small children and small animals. For instance pets have become seriously ill or died from ingesting small amounts of antifreeze.
Young children should not play near chemical storage or anywhere chemicals are handled. Even lawn and garden chemicals can be dangerous if a small child walks barefoot through a treated lawn or garden.
If you plan to use chemicals on your yard, acreage, or home, be sure to do so safely. Follow these important guidelines:
- Do not allow young children to handle chemicals. Train older youth to use and handle chemicals safely.
- Know the protective gear you need and wear it. Include appropriate gloves, masks if needed, shoe covers, goggles, long sleeves, long pants and other gear as needed.
- Wash thoroughly after handling chemicals, that is, scrub hands and any part of your body that was in contact with chemicals, for 20 seconds or more. Use soap and rinse with hot water.
- Launder clothes used when handling chemicals separate from household laundry. Wash soon after contamination, using a pre-wash, hot water, heavy-duty detergent, and a normal wash cycle. Line dry to break down any remaining chemical. Rinse your washer before doing regular laundry.
- Store all chemicals in their original containers with original labels and cautionary statements. Do not discard labels. Many chemicals look like food we eat – NEVER use food containers, like soda bottles or frozen food bowls, to store chemicals.
- Store chemicals separate from other household or work containers, preferably in their own cupboard or small building. Lock and clearly mark the areas.
- Make it a habit to keep out of treated areas for at least 24 hours. Check labels for longer times which may be required.
- Learn first aid for chemicals in order to be able to help someone who may be exposed to a harmful chemical.
The safest way to handle the chemicals is with precaution and protection. Learn about the chemicals you are using in your home and on your farm. Then insist on protective gear and training for anyone handling any chemicals.
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4. Aerate Or Power Rake Lawns, Or Both
By Kelly Feehan, UNL Extension Educator
April is just around the corner and with it comes the start of lawn care. Fertilization should be delayed until after mid-April to allow soil temperatures to warm for healthy root growth; but don't wait until April to hand rake leaves and other debris from the lawn. The sooner this is done, the better.
Once hand raking is completed, the next two lawn care practices to consider are core aeration or power raking. Both practices can be done from late March through April, or in September. If completed in spring, it's important to allow soil to dry before doing either practice.
Core aeration removes cores of soil to relieve soil compaction which occurs from irrigation, foot, and mower traffic. Aerate once a year on lawns growing on silty loam or clay soils and those which have a lot of foot traffic; i.e. your kids like to run through the sprinklers on hot days or you often entertain. Lawns on sandier soils and having little foot traffic can be aerated less often.
By relieving soil compaction, the infiltration of water, fertilizers, and soil applied pesticides is improved. Pore spaces in soils are enlarged to improve water drainage and increase oxygen levels. And thatch builds up more slowly. This promotes deeper, healthier roots which leads to healthier top growth and fewer diseases, insects, and weeds.
Power raking is recommended to reduce true thatch once the layer exceeds one-half inch. True thatch cannot be seen from the lawn surface. Some people power rake for cosmetic reasons. Their goal is to remove some of the dead debris they can see on the surface of the lawn. In these cases, the lawn is given a light power raking.
True thatch is a reddish brown mat found between the soil line and turfgrass crowns. It consists mainly of roots, rhizomes and stems. Grass blades contribute little to thatch and so thatch builds up whether grass clippings are caught or left during mowing.
A one-half inch layer of thatch is beneficial. It acts as an insulation layer for the growing crowns from extreme heat and cold, and foot traffic. If a lawn is power raked too often and too deeply, this true thatch layer may not build up to a beneficial point.
Once the layer exceeds one-half inch, thatch becomes detrimental to turfgrass. Roots tend to grow in thatch instead of the soil, water does not infiltrate as readily, and fertilizer and pesticides can become tied up in thatch.
Check your true thatch layer about once a year and check for it in more than one area of the lawn. To measure true thatch, cut a small pie-shaped wedge, or plug and pull it from the lawn. Look for the reddish brown mat between the soil line and the green grass, then measure it.
If true thatch is greater than one-half inch thick, it's time to think about power raking. However, don't forget to core aerate. Aeration is one of the most beneficial practices you can do for a healthy lawn and it should be done about once a year whether you power rake or not. Core aeration also slows down the build up of thatch. If it's done often, a deep power raking may rarely be needed.
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5. Hardening Transplants
By Don Janssen, UNL Extension Educator
The term "hardening" refers to any treatment that results in a firming or hardening of plant tissue. Such a treatment reduces the growth rate, thickens the cuticle and waxy layers, reduces the percentage of freezable water in the plant and often results in a pink color in stems, leaf veins and petioles. Such plants often have smaller and darker green leaves than nonhardened plants. Hardening results in increased carbohydrates in the plant permitting more rapid root development than occurs in nonhardened plants.
Any of the following can be used to harden transplants. A combination of all these techniques at one time is more effective.
- Gradually reduce water - water lightly at less frequent intervals but do not allow the plants to wilt severely.
- Expose plants to lower temperature than is reported as optimal for their growth. If biennials are exposed to cold for an extended period, they may bolt instead of developing properly. Note: Placing the plants outside during the day to encourage hardening and then bringing the plants back into the warm house during the night often reverses the hardening process. Plants could be placed in a cold frame or other area that does not freeze during the night hours without interruption of the hardening process.
- Do not fertilize, particularly with nitrogen immediately before or during the hardening process. However, a starter solution or liquid fertilizer could be applied to the hardened transplants one or two days prior to transplanting into the garden or at the time of transplanting.
- Gradually expose the plants to more sunlight. This results in the development of a thicker cuticle layer thereby reducing water loss.
Warm-season types of plants even when hardened, will not withstand temperatures much below freezing.
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6. Planting Garlic
By Kelly Feehan, UNL Extension Educator
If you missed planting garlic last fall, you can still plant it this spring but the earlier the better. Garlic is as easy to grow as onions and will produce well in Nebraska if planted in mid-October, or from March into early April. Onions can be planted throughout April.
Fall or very early spring planting is required for garlic because dormant cloves and young garlic plants must be exposed to temperatures of 32-50°F for one to two months to induce bulb formation. In most cases, you will have the best success with fall planting.
Garlic is started from cloves (bulbils) because most garlic flowers are sterile and will not produce true seed. Just before planting, separate bulbs into individual cloves. Do not divide the bulbs more than a few days before planting as early separation can decrease yields.
Garlic grows best in fertile, well drained, friable loam soils high in organic matter. If you are successful in growing onions, your soil should be fine for garlic.
If your soil is high in sand or clay, add organic matter to break up clay soil for better drainage and to improve the water and nutrient holding capacity of sandy soils.
Add organic matter by spreading one to three inches of well rotted organic matter over the soil surface. Use a spading fork to turn over and break up the soil and to mix in the organic matter. A roto-tiller can be used to prepare soil, but keep in mind that over-tilling can destroy soil structure.
Whether you planted garlic last October or you plan to plant now, pay attention to watering and fertilization this spring. Like onions, garlic needs a steady supply of nutrients while actively growing. This is because their roots lack the root hairs that aid most plants in nutrient absorption.
When preparing the soil prior to planting garlic or onions, apply 3 to 4 pounds of 10-10-10 fertilizer per 100 square feet, along with organic matter, and work it in. Once vigorous leaf growth begins, several light applications of nitrogen are better than a few heavy applications; especially on sandy soils where nitrogen is easily leached out of soil.
When planting garlic, use the largest cloves for planting and save the smaller cloves for cooking. The opposite is true for storage onions and shallots. With these, plant the smallest onion sets for storage bulbs. Plant the largest sets closer together to harvest for green onions.
When planting, take care not to plant garlic cloves so deep that soil hampers expansion of the bulb. It’s also important not to plant so shallow that rain washes the cloves out of the soil. Plant the cloves 3 to 5 inches apart, with the pointed end up, and 2 to 3 inches deep.
Garlic is sensitive to drought. One inch of water per week is required and it is important to keep the soil uniformly moist. Garlic has shallow roots and dry soil will result in irregularly shaped bulbs.
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7. Arbor Day & Tree Planting Tips
By Kelly Feehan, UNL Extension Educator
Arbor Day is a holiday that celebrates Nebraska’s past while preparing for the future with tree planting. Arbor Day is this Friday, April 27, and this is a great time to plant trees.
For tree planting success, select the right tree for your location. Determine if the tree will tolerate the growing conditions of your site and perform the landscape function you need.
For some ideas on trees to grow, contact your local UNL Extension Office for their list of desirable trees or refer to the Nebraska Statewide Arboretum website at http://arboretum.unl.edu. You can also check with your local nursery or garden center.
When buying trees, select trees with a single straight trunk unless you are buying a multiple stemmed tree, i.e. river birch. Look for trees that have branches evenly distributed around the trunk and the branches are not more than 2/3 the diameter of the trunk.
Avoid trees with double leaders and whose trunks are tightly staked in the container. Avoid trees with very narrow branch forks where there may be included bark, and look for damage to the trunk.
Handle trees carefully when transporting them. Protect tree canopies from wind damage while transporting them to your home. Avoid dropping them or damaging their trunk and central leader. Do not let the root ball dry out. Carry trees by the container or the root ball and not by their trunks as this can damage the trunk and roots.
At planting time, keep in mind the majority of roots grow outward and in the upper 8 to 10 inches of soil. Dig the hole wider then the root ball but no deeper. This will encourage root growth by loosening the soil beyond the root ball. It will also prevent the tree or soil from settling too much after planting so the tree ends up being too deep.
A key point when planting trees is not to plant too deep. Trees planted too deep may experience root dieback creating greater transplant shock; and tend to be less vigorous and more susceptible to diseases and insects throughout their life.
Trees make it fairly easy for us to determine how deep to plant them. At the base of the trunk, the trunk widens and tapers slightly outward. This area is called the root flare or trunk taper. At this point is also the first lateral root or the root closest the surface of the root ball.
When planting, the trunk taper should be visible just above the soil line and the first lateral root should be just below the soil line. In poorly drained, clay soils, planting so the trunk taper is one to two inches above the soil is advised.
Except in cases where soil is extremely poor, it’s best to backfill the planting hole with the same soil that was removed rather then amending the soil of the hole too much. Roots tend to grow in this ideal soil and not out into surrounding soil. As you backfill, settle the soil by watering, rather than tamping with your foot which compacts soil.
As a rule, most Nebraska soils are fertile enough to support tree growth. Except in very low fertility soils, do not apply nitrogen fertilizer at planting time. Nitrogen may burn young roots or result in vegetative top growth at the expense of roots.
How about a starter fertilizer containing phosphorous? Again, the fertility of most Nebraska soils will support tree growth. A starter fertilizer is usually not needed, but may be beneficial when planting into cold, compacted, or low fertility soils.
After planting and watering, apply a two to four inch layer of organic mulch in at least a four foot diameter ring around the tree. Mulch conserves water, keeps weeds and grasses from growing next to the tree, and protects the trunk from lawn mowers and grass trimmers. It is important to keep mulch a few inches away from the trunk and not apply it too deeply.
In windy Nebraska, it’s a good idea to stake larger trees growing in windy locations. If you stake, use staking and guying materials that will not rub and injure the trunk. Stake as low on the trunk as possible to allow the top half of the tree some movement. The goal of staking is to prevent the root ball from shifting too much and tearing new roots.
Throughout the growing season, water new trees with about one inch of water per week. At each watering, moisten the soil six to eight inches deep and be sure to moisten the soil outside the root ball to encourage outward root growth. Allow the soil to dry slightly before watering again, and remember that overwatering is just as harmful as underwatering.
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8. Tree Selection- The Right Tree In The Right Place
By John Wilson, UNL Extension Educator
Tree selection is one of the most important investment decisions a homeowner makes when landscaping a new home or replacing trees. Most trees outlive the people who plant them. Consequently, it is important to match the tree to the planting site.
The most frequently asked question is, "What tree should I plant?" Before this question can be answered, you must address the following:
- Why is the tree being planted? Do you want the tree to provide shade, fruit, or seasonal color, or act as a windbreak or screen?
- What is the size and location of the planting site?
- Does the space lend itself to a large, medium, or small tree?
- Are there overhead or below ground wires or utilities in the vicinity?
- Do you need to consider clearance for sidewalks, patios, or driveways?
- Are there other trees in the area?
- What soil conditions exist? Is the soil deep, fertile, and well drained, or is it shallow, compacted, and infertile?
- What type of maintenance are you willing to provide? Do you have time to water and prune the newly planted tree? If not, will you rely on a professional tree business for assistance?
Properly placed and maintained trees increase real estate value. A large shade tree provides relief from the summer's heat and, when properly placed, can reduce summer cooling costs.
An ornamental tree provides beautiful flowers, leaves, bark, or fruit. Evergreens with dense, persistent leaves can provide a windbreak or a screen for privacy. A tree that drops its leaves in the fall allows the sun to warm a house in the winter.
A tree or shrub that produces fruit can provide food for the owner and/or attract birds and wildlife. Trees reduce the glare from pavement, reduce run off, filter out pollutants, and add oxygen to the air we breathe. Trees also improve the quality of life on our property.
Frank Lloyd Wright, the famous architect, once commented that "form follows function." This is a good rule to remember when selecting a tree. Selecting the right form (shape) to complement the desired function (what you want the tree to do) can reduce maintenance costs and increase the tree's value in the landscape.
When selecting a tree, consider its mature size. Trees grow in a variety of sizes and shapes that will fit the planting space available. Depending on your site restrictions, there are hundreds of combinations of form and size from which to choose.
You may choose a small spreading tree in a location with overhead utility lines. You may select a narrow columnar form to provide a screen between two buildings. You may choose large vase-shaped trees to create an arbor over a driveway. You may even determine that the site does not have enough space for a tree of any kind.
Beware of magazine and newspaper advertisements for "super trees." "Super trees" usually have faults not mentioned in the advertisements that should be investigated before purchase. Unsuspecting buyers are lured by vivid descriptions of amazing growth and beauty.
Generally, these ads refer to the tree by scientific name only or by an unfamiliar species name. These advertisements are full of exaggerations, such as "the tree soars into a magnificent tree in just one year." Also, the price is often exorbitant for the size and species of tree being promoted.
Visit with someone from a reputable nursery, or several nurseries, and get their suggestions for trees that will meet your goals and are best suited for your site. They will want the information from the questions above before making their recommendations. You can also contact your local University of Nebraska-Lincoln Extension office.
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9. Pest Monitoring
By Kelly Feehan, UNL Extension Educator
When it comes to controlling plant pests, like diseases and insects, the timing of control is critical in determining how successful we’ll be in reducing the pest or preventing plant damage.
A common reaction to pest problems is applying a pesticide such as a fungicide or insecticide. However, when we first notice damage the time for effective control using pesticides may be past, or when we first notice the pest it may not be the correct time to apply a pesticide.
It’s helpful to be aware of potential plant pests and monitor for them. It’s also helpful to understand the life cycles of pests and to know at what stage they can damage plants, as well as at what stage they are susceptible to control. Following are some examples.
Annual white grubs can be found in gardens and lawns now; however, these full grown grubs do not cause damage at this time of the year. Also, applying an insecticide now is not effective in killing full grown grubs and will not control the next generation that can damage lawns in summer.
The time to apply control for white grubs is based on what product is used. Imidacloprid, or Merit, needs to be applied before the eggs hatch, ideally in June. If Dylox is used, this insecticide must be applied after the eggs hatch in early August to be effective.
In contrast, spruce mites are beginning to hatch now and are feeding on the sap of evergreen trees. However, they are so tiny they are difficult to see and the damage they cause often does not appear until summer when infested trees begin to turn off-color and then brown.
By the time spruce mite damage appears, the mites have done their damage and are gone or in the egg stage. Applying an insecticide during summer will not control spruce mites or prevent their damage.
Now is the time to check spruce trees for spruce mite. To do so, gently shake a few branches over a white sheet of paper. Watch the specks on the sheet of paper. If they begin to crawl after a few seconds, this is an indication spruce mites are present.
To confirm the specks or spruce mites, and not just the wind blowing specks of dirt around, smear the specks with your finger. If they smear red or green, they are most likely a mite.
To control spruce mites, hose the tree down with water or apply a dormant or horticultural oil to the tree before bud break. Be aware that horticultural oils will cause blue spruce to lose their blue color for one growing season.
Other controls for spruce mite include insecticidal soaps and systemic insecticides, such as Acephate, that are labeled for use on evergreen trees.
Another example is summer patch disease of lawns. This fungal disease infects the roots of turfgrass during May, but summer patch symptoms do not appear until the grass is under heat stress during late June through August. If a homeowner needs to apply a fungicide to control summer patch disease, the application needs to be made in May and repeated once or twice to be effective in reducing this disease.
If you notice plant problems during the growing season, remember to positively identify the cause of the problem and determine if the pest can cause unacceptable damage. If a pesticide is chosen as a control method, be sure to apply it at a time when it will be effective.
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10. UNL Soil Fertility Web Site
By Charles Shapiro, UNL Soil Scientist
Need information on soil fertility or testing? Visit UNL Soil Fertility online and click on 'Soil, Manure and Plant Analysis'. At the University of Nebraska-Lincoln Soil and Plant Analysis Laboratory (SPAL), you can print off submittal forms for soil and water sample analysis, and check the current prices for testing.
UNL Soil Fertility, http://soilfertility.unl.edu
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