Madison County Energy Conservation Study 2012-2013 Survey of Roadside Vegetation.

摘要

The current clear zone mowing frequency for I-10 in Madison County (FDOT Maintenance District 2) is 7 times per year. To conserve energy and reduce expenses associated with mowing, a pilot study was implemented in 2009, and continued in 2010-11 (Contract No. PR4170440) and 2012-13 (current contract). In cooperation with District 2 maintenance personnel, mowing of the westernmost mile of I-10 in Madison County was limited to a 10- to 15-ft safety strip along the edge of pavement until the time of the fall cleanup mowing. As was done from 2009 to 2011, vegetation surveys of the clear zone were conducted by walking forays twice per year spring (March) before the first safety strip mowing and fall (October) just before the cleanup mowing. The main objectives were 1. Document the presence and approximate extent of (a) desirable and showy native wildflower and grass species, and (b) nonnative species, especially those listed as undesirable by FDOT Maintenance Rating Program (MRP) standards, and 2. Suggest management practices for the predominant species in the clear zone. In addition, soil characteristics were recorded in fall 2012 and 2013 where Bidens alba (Spanish Needles) was abundant. This species is of special concern because FDOT anecdotal evidence suggests that it causes erosion. However, no erosion has been noted in the pilot study, even where Bidens alba was dense. The relationship between this species and erosion may be due to soil characteristics. The modified mowing regime has not and is not expected to interfere with normal highway operation in the near future. The widespread occurrence of the MRP undesirable species Ambrosia artemisiifolia (Common Ragweed), Bidens alba, Eupatorium capillifolium (Dogfennel), and Paspalum urvillei (Vaseygrass) has not resulted in any erosion, or sites likely to erode. Moreover, in locations where non-turfgrass species may be outcompeting traditional turfgrass species, the non-turfgrass species appeared to have provided the same soil stabilization functions of traditional turfgrass species.