VANDER-01-003

The Use of Mats to Reduce Grass Competition
Sponsor: 
Vanderwell Contractors (1971) Ltd.
Lead Researcher: 
Brian Makaruk for Vanderwell Contractors (1971) Ltd., Alberta
Body: 
This study explored the ability of Tredegar mats to suppress growth of established Calamagrostis canadensis around planted seedlings.

Between July 31 and August 4, 1995, approximately 3,000 white spruce containerized seedlings were planted in a six-year-old block south of Slave Lake. Planters screefed a 30cm x 30cm patch through the established Calamagrostis canadensis sod and planted a seedling in the centre of the screefed patch. The planters then pushed down the grass outside the screef and installed a 90cm x 90cm Tredegar mats around each seedling.

The survival rate of the seedlings three years following planting was 23%, with surviving seedlings showing poor growth in both height and root collar. The mats were ineffective in controlling established Calamagrostis canadensis, however may be more effective if installed prior to establishment. Seedlings in plots located in an adjacent block exhibited better growth and survival, demonstrating the effectiveness of excavator mounding site preparation in controlling Calamagrostis canadensis.