mgconferences

How Can I Control Clover In My Lawn?

Clover is a bit like wild violets in the lawn - you have to decide whether you consider it a weed or a flower to be enjoyed. Personally, I leave some clover in the lawn for the rabbits and hope that they'll feed on it and perhaps leave my perennials and annuals alone! Clover is a legume, and so it also fixes nitrogen in the soil, as well.

However, if you decide to control clover, you are looking at a couple of opportunities - one in the mid-May to mid-June period when most weeds are actively growing, temperatures are moderate, and moisture adequate in the root zone. The other time is late summer, about mid-September to mid-October before it gets too cool.

Clover and wild violets are lawn weeds that are considered "difficult to control," and the usual home use broadleaf weed herbicides don't do much against them. In June 1995, wild violet control was evaluated at the Ohio State University. Herbicides evaluated in this study included 2,4-D, MCPP, dicamba, and triclopyr. Data collected seven weeks after treatment showed that 2,4-D, MCPP and dicamba only provided 18.3% - 30.0% control following a single application, whereas the best control was achieved using triclopyr, resulting in 81.7% control. For wild violet, white clover and other difficult weeds such as and ground ivy, try a product that contains triclopyr. Triclopyr is available on the homeowner market, and often lists the weeds controlled on the front label, so it's easy to find. Check the active ingredient statement on the back to make sure it is triclopyr.

Surface Roots on Two Maple Trees in My Front Yard are causing a Mowing Problem. Is there a solution?

Many gardeners are faced with the problem of tree surface roots. These are difficult to mow or walk over, and can lead to decline and death of nearby grass or groundcovers. Gardeners often attempt to remedy the situation by adding fill soil over the roots and then replanting grass or groundcover. However, this addition of soil reduces the concentration of soil oxygen needed by roots to survive, and the tree will begin to show symptoms of decline over time; sometimes this occurs immediately, and sometimes it occurs over a period of years. Visible symptoms of injury may include small, off color leaves, premature fall color, suckering along the main trunk, dead twigs throughout the canopy of the tree, or even death of large branches.

Injury will vary by tree species, age, health of the tree, depth and type of fill, and drainage. Trees that are usually severely injured by additional fill include sugar maple, beech, dogwood, many oaks, pines and spruces. Birch and hemlock seem less affected, and elms, willow, London planetree, pin oak and locust seem least affected. Older trees and those in a weakened state are more likely to be injured than younger, more vigorous trees.

A better way to deal with surface roots is to cut a bed around the offending root system, and cover with a coarse mulch. Trying to establish grass or groundcover in among surface roots is often difficult, if not impossible to do.

The Master Gardener Offers horticulture advice and tips, focusing on current issues by volunteers who are with The Ohio State University Extension, Union County Master Gardener Program. For answers to gardening questions, call 937.644.8117 or e-mail gmcvey@ag.osu.edu. Hourse are 8 a.m. to 4:30 p.m. Monday through Friday