Research and Updates

Robotic Weeder

Suppress 

During a control efficacy trial conducted at the CREC Suppress EC was demonstrated to control up to 85% of weed grass growth in the field, specifically barnyardgrass. During this trial, an 18% v/v mixture of Suppress with a water carrier of pH 2.8 was used to yield these results. It is important to ensure that the water carrier is of a pH < 3; pH of water carrier can be lowered using products high in citric acid such as lemon juice.

When tested in greenhouse trials, results indicated that Suppress EC works best on plants 7cm in height or less. Results also demonstrated close to 100% control of palmer amaranth 5cm in height and approximately 90% control of palmer amaranth 7cm in height. Suppress EC also performed about 30% better than Scythe at controlling 10cm palmer amaranth.

 

Cryogenic Weed Control

Cryogenic weed control is accomplished by freezing the exposed tissues of weeds before destroying them with mechanical pressure. Freezing of plant tissue is done by spraying plants with liquid nitrogen and destruction of plant tissue is carried out by using a ballasted roller. The mechanical pressure of the roller not only fractures the exposed frozen plant tissue but also disrupts organelles in young leaves and meristematic tissue below the ground.

Based on trials carried out to test control of morning glory, the best results were obtained when using a brass nozzle affixed 30cm above the ground applying a high output of liquid nitrogen (9360l/a) at a high pressure (41kPa).

Cryogenic weed control is a potentially more sustainable management method in the long run compared to using herbicides. This is because liquid nitrogen leaves no chemical residues and does not affix nitrogen to the soil. In addition, this method is fueled by a readily available resource in atmospheric nitrogen.

 

Anaerobic Soil Disinfestation

Here at CREC, this technique's viability as a means of non-chemical weed control is now being investigated. As it has already been noted as being an effective means of preventing grass and nutsedge growth when planting tomatoes, strawberries, eggplant, peppers, and cucurbits, further test will be carried out testing this technique's viability as an effective non-chemical weed management technique. 

 

Robotic Weed Control

The robotic weeding trials to be carried out will be done using the Husky unmanned ground vehicle. This UGV will be equipped with cotton harvesting equipment in addition to a sprayer for herbicide application. It will be outfitted with a mechanical actuator for accurate herbicide spraying as well as equipment to be used for cotton harvesting. 

 

Cover Crops

Cereal ryegrass has been shown to reduce wild mustard proliferation by about 70% 

Regal Graze Ladino Clover 12-15 lbs /ac reduces sedge by 70% and corn spurry by 80%

Red Clover reduces corn spurry spread by 75% and wild mustard growth by 80%

Rye grass

Figure 1: Ryegrass Cover

Ryegrass being used to control wild mustard proliferation.

Ledino clover

Figure 2: Ledino Clover Cover

Ledino clover being used to control corn spurry proliferation.

Red clover

Figure 3: Red Clover Cover

Red clover mulch being used to control corn spurry and wild mustard proliferation.

Crimped rye grass

Figure 4: Crimped Ryegrass

Sweet potatoes planted into crimped ryegrass cover crop.

Crimped ryegrass photo credits: Dave Robb and Geoff Zehnder