Selection, Establishment and Maintenance of Woody Ornamental Plants for Highway Plantings

Abstract

The effect of shredded wood bark, shredded rubber tires and Douglas fir bark chips, used as mulches, on weed control and growth of landscape plants was evaluated. Long lasting weed control (2 seasons) was achieved with of Douglas fir bark and 1 inch and 2 inch of shredded rubber mulch. Weed control would decrease over a longer period of time with Douglas fir bark due to decomposition, however decomposition would not affect the shredded rubber tire mulch. Growth of landscape plants did not appear to be reduced with any mulch. Studies were conducted to determine the effect of shredded rubber tire mulch, Douglas fir bark, stone and stone over black plastic on soil moisture and temperatures. Shredded tire, Douglas fir bark and stone over plastic had noticeably higher moisture levels than either bare soil or soil covered with stone. The use of mulch modified soil temperature. There appeared to be very little difference in mulches as far as their effect on soil temperature was concerned. /Author/