Weed Management

Weeds are widespread in many orchards. If not managed properly, however, they can have a serious economic impact with crop losses and increased production costs. On this page, find educational resources on weed management and control in fruit crops, including herbicides and pesticides advice. Tips on avoiding herbicide drift are also available.

Fruit Crop Weeds

Weeds in orchards are a major concern in the fruit production industry. These plants often compete with fruit crops for nutrients, water, light, and space. Without adequate management, weeds can lower yield and serve as hosts for pests, insects, and diseases. In addition, weeds can interfere with fruit harvest and produce chemical substances (allergens and toxins).

Weeds are commonly categorized according to their life cycles (annuals, biennials, and perennials). Prevalent orchard weeds include Daucus carota (also known as Wild Carrot or Bird's Nest) and nutsedge.

A way to identify and assess weed problems in orchards is by periodically scouting the orchard during the growing season. Weed scouting resources in Spanish are available, as well.

Weeds Control and Management

For successful fruit production, unwanted weed plants need to be managed in an economical and practical way. Sound weed management typically involves an integrated approach using a variety of weed control methods.

Common management tactics include weed prevention, avoidance, and suppression, as well as mechanical and chemcial control (herbicides). Applying herbicides can also be part of an IPM plan for orchard pests such as rodents and cat-facing insects.

The first step to managing weeds is gaining insights on possible orchard weed control strategies by identifying the species present and the extent of the spread.

Discover more information and advice with Penn State Extension’s detailed guide to creating a weed management plan for organic farms. Additionally, access up-to-date information for growing fruit commercially and discuss current tree fruit issues with Extension specialists and fellow growers at one of the spring orchard meetings.

Fruit Crops Herbicide Application

Herbicides are convenient and effective chemicals used to eliminate weed plants. Applying herbicides in the fall plays an important role in successful weed management. Fall herbicides aid spring and summer weed control by delaying spring application time and controlling winter annuals. Effective fall applications typically begin by scouting the orchard to identify whether the weeds are predominantly annuals, perennials, or a mix of both.

Herbicide Drift

Herbicide drift refers to the movement of pesticides away from the target area. In general, all pesticides are capable of drifting, which is why it’s the applicator’s responsibility to prevent drift and avoid contaminating or damaging nearby crops. Certain plants such as fruit trees, watermelons, and grapes are more susceptible to herbicide drift.

Drift can occur in two ways – vapor or particle. To reduce damage from particle drift, it’s advised to spray in low winds and use air induction and/or low-pressure nozzles. To minimize vapor drift in warm temperatures, it is recommended to use amines instead of esters.

Find further resources on weeds management, herbicides, and drift prevention with Penn State Extension resources. Practical information on spray record keeping, as well as private pesticide application training, is available, as well.