WEST VIRGINIA APPLE CROP PROFILE
Weeds
Weeds are an important pest problem in West Virginia apple orchards because they: 1) compete with the tree for water and nutrients; 2) can interfere with pollination if their flowering period coincides with apple bloom; 3) can interfere with harvest (poison ivy and brambles); and 4) can harbor insects, rodents and diseases that can affect fruit trees.
Chemical control: Most fruit growers apply a combination of contact and residual herbicides in a single application per year for the control of grasses and broadleaf weeds within the tree row. This may be followed by a second application of contact herbicide throughout the orchard, or as a spot treatment for perennial weed problems.
|
|
|
Amount used |
Herbicide |
% of acres treated |
lb a.i./acre/year |
| 2,4-D | 33 |
1.83 |
Diuron |
25 |
3.12 |
Glyphosate |
5 |
1.31 |
Norflurazon |
5 |
2.91 |
Paraquat |
64 |
1.12 |
Simazine |
33 |
2.77 |
Terbacil |
6 |
1.01 |
Cultural control: In some orchards, especially those on more sloping sites, ground vegetation may exist within the tree row that is managed with mowing. Alley ways between the tree rows typically consist of Kentucky-31 tall fescue that is managed with mowing.
Critical uses and needs
Herbicide use to manage weeds within the tree row is an important component of an IPM program for rodents by creating a less desirable habitat for voles which can cause significant tree losses. Management of weeds with herbicides is also especially important in newly established orchards so that tree growth is not impaired and trees can fill their growing space as quickly as possible.