The overall appearance of a lawn is directly related to the maintenance provided. September is an ideal time for many lawn maintenance practices?such as weed control. To have additional questions answered, contact the horticulturists at hortline@iastate.edu or call 515-294-3108.

When is the best time to apply a herbicide to the lawn to control dandelions and other broadleaf weeds?

Fall (mid-September through October) is the best time to control perennial broadleaf weeds in the lawn with broadleaf herbicides. In fall, perennial broadleaf weeds are transporting food (carbohydrates) from their foliage to their roots in preparation for winter. Broadleaf herbicides applied in fall will be absorbed by the broadleaf weed's foliage and transported to the roots along with the carbohydrates, resulting in the destruction of the broadleaf weeds.

Broadleaf herbicides can be applied as liquids or granules. Before applying any herbicide, carefully read and follow label directions.

What is the proper way to apply broadleaf herbicides to the lawn?

Broadleaf herbicides can be applied as liquids or granules. Before applying any herbicide, carefully read and follow label directions. When applying liquid formulations, potential spray drift problems can be avoided by following simple precautions. Don't spray when winds exceed five miles per hour. Also, don't spray when temperatures are forecast to exceed 85 degrees Fahrenheit within 24 hours of the application. Since coarse droplets are less likely to drift than fine sprays, select nozzles that produce coarse droplets and use low sprayer pressure when applying liquid broadleaf herbicides. When spraying, keep the nozzle close to the ground. If only a few areas in the lawn have broadleaf weed problems, spot treat these areas rather than spraying the entire lawn. Apply just enough material to wet the leaf surfaces.

Granular broadleaf herbicides are often combined with fertilizers. Apply granular broadleaf herbicides and fertilizer/broadleaf herbicide combinations when the weed foliage is wet. Broadleaf herbicides are absorbed by the weed's foliage, not its roots. To be effective, the granules must stick to the weeds and the herbicide must be absorbed by the weed's foliage. Apply granular products in the early morning when the foliage is wet with dew or irrigate the lawn prior to the application.

To ensure adequate leaf surface and herbicide absorption, don't mow the lawn two to three days before treatment. After treatment, allow three or four days to pass before mowing. This allows sufficient time for the broadleaf weeds to absorb the herbicide and translocate it to their roots. To prevent the broadleaf herbicide from being washed off the plant's foliage, apply these materials when no rain is forecast for 24 hours. Also, don't irrigate treated lawns within 24 hours of the application.

How do I control creeping Charlie in my lawn?

Ground ivy ("creeping Charlie") in lawns can be controlled with broadleaf herbicides. Products that contain 2,4-D or triclopyr are most effective. 2,4-D is an active ingredient in many broadleaf herbicide products. Triclopyr can be found in Ortho Weed-B-Gon Chickweed, Clover, and Oxalis Killer for Lawns and a few other products. In Iowa, herbicide applications should be made between mid-September and Nov. 1. Two applications are necessary to effectively control ground ivy. The first application should be made in mid to late September, the second a month later.

How do I control violets in my lawn?

Violets are very difficult to control. Digging up the plants is an option for home gardeners with a small infestation of violets. Broadleaf herbicides are the most practical solution when dealing with large numbers of violets. Broadleaf herbicides containing triclopyr usually provide good control of violets. Applications can be made in spring (during bloom) or fall. Two applications, two to three weeks apart, are usually necessary to achieve good control.

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The current national soybean yield average is 44 bushels per acre, but to meet world demand, that figure needs to be boosted to 59.5 bushels per acre by the year 2030. The checkoff's Production Research program funds research utilizing soybean genomics to help meet this goal.

A new checkoff project will use the mapped soybean genome to accelerate the process of developing and introducing new traits that could lead to high-yielding varieties.

Click here to download an audio news report with USB Production Research program Chair Jason Bean, a soybean farmer from Missouri, discussing how says the checkoff supports research that utilizes the mapped soybean genome to identify and evaluate specific soybean genes that increase yields.

If you would like to conduct additional interviews, please call Erin Hamm at 888.235.4332 or e-mail your request to hamme@osborn-barr.com.

The garden peony is a popular, long-lived perennial that provides abundant flowers in spring and attractive foliage throughout the growing season. If given a good site and proper care, an established peony will flower for many years. To have additional questions answered, contact the horticulturists at hortline@iastate.edu or call 515-294-3108.

When is the best time to transplant peonies?

September is the best time to transplant peonies. Begin by cutting the peony stems near ground level. Then carefully dig around and under each plant. Try to retain as much of the root system as possible.  Promptly replant the peony in a sunny, well-drained site.

What would be a good planting site for peonies?

Peonies perform best in full sun and well-drained soils. When selecting a planting site, choose a location that receives at least six to eight hours of sunlight each day. Avoid shady areas near large trees and shrubs. Poorly drained soils can often be improved by working in large amounts of compost, peat moss or leaf mold.

What is the proper way to divide peonies?

September is the best time to divide peonies. The first step is to cut off the peony stems near ground level. Then carefully dig up the plant. Gently shake the clump to remove loose soil from the root system. Using a sharp knife, divide the clump into sections. Each division should have at least three to five buds (eyes) and a good root system. Smaller divisions will require several years to develop into attractive plants.

When planting a peony, dig a hole large enough to comfortably accommodate its entire root system. Position the peony plant in the hole so the buds are 1 to 2 inches below the soil surface (peonies often fail to bloom satisfactorily if the buds are more than 2 inches deep). Fill the hole with soil, firming the soil around the plant as you backfill. Then water thoroughly. Space peonies 3 to 4 feet apart.

Is it necessary to periodically divide peonies?

Peonies do not need to be divided on a regular basis. Peonies can be left undisturbed in the garden for 50 or more years. However, large, vigorous peonies can be divided if you want additional plants.

When should I cut back the peony foliage?

Peony foliage should not be cut back until it is destroyed by a hard freeze in fall. The foliage manufactures food for the plant. Some of the food is stored in the plant's root system. The more food the peony plant can store in its roots, the better the flower display next spring. Cut off the peony stems at ground level in late October or November. Remove the peony foliage from the garden and destroy it. The removal and destruction of the peony debris helps to control leaf blotch and other fungal diseases.

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