Fowl Meadow Grass (Poa Palustris) Control in an Established Alfalfa and Timothy Crop

Other names: Fowl bluegrass, June grass

The Weed: Perennial, with a membranous ligule and rough textured, folded leaves. Mature plants are yellowish in colour. The stems are round and purplish at the base.

The Impact: Fowl meadow grass grows incredibly fast and has usually headed by the third to fourth week in May. As the species gets older it turns a yellowish colour and the stems become very coarse and wirey, this usually occurs before the alfalfa and timothy is ready for its first cut. This weed affects forage value as palatability can be

decreased and often clients purchasing feed for the horse market do not like the appearance of this grass (See Figure 1).

Control Options (Preliminary Research). A field trial was conducted in the spring of 2007 to evaluate efficacy of Fowl meadow grass, tolerance of alfalfa and timothy with 15 herbicide treatments. While there were many products that controlled Fowl meadow grass only 1 treatment, Achieve + Turbocharge (Figure 2), provided both adequate crop safety and weed efficacy (Table 1).

Table 1 - Percent visual control of Fowl meadow grass and percent visual injury of alfalfa and timothy at 3 weeks after application of 3 herbicide treatments.

Treatment

Rate/acre

Fowl meadow grass control (%)

Alfalfa Injury (%)

Timothy Injury (%)

Achieve + Turbocharge

200 ml/ac + 0.5% v/v

76

0

0

Venture

240 ml/ac

99

0

64

Poast Ultra + Merge

133 ml/ac + 0.5% v/v

97

0

93

Source: Swanton and Tardif, 2007 Weed Research Report – Trial #07POAPA31JN

Registration Status: Achieve is not registered for use on alfalfa or timothy for forage production. Crop residue data is required before a registration can be pursued however collection of residue data is very expensive and unlikely to be initiated by the manufacturer based on a limited number of acres being affected with this grassy weed. Growers who would find value in controlling Fowl meadow grass in forage crops should send letters of support for this project to the Ontario Forage Council c/o Agricultural Services Centre, Box 463, 206 Toronto Street South, Markdale, Ontario  NOC 1HO. 

Limitations: This is a preliminary study and more trials are needed to gain confidence that these results can be duplicated under various environmental conditions.

Fowl meadow grass infestation in an alfalfa/timothy stand.

Figure 1. Fowl meadow grass infestation in an alfalfa/timothy stand.

Fowl meadow grass control with Achieve + Turbocharge. Note the presence of timothy in the treated area.

Figure 2. Fowl meadow grass control with Achieve + Turbocharge. Note the presence of timothy in the treated area.

Fowl meadow grass control with Poast Ultra.

Figure 3. Fowl meadow grass control with Poast Ultra.

Note the absence of any timothy in the treated area

 


For more information:
Toll Free: 1-877-424-1300
E-mail: ag.info.omafra@ontario.ca