THE EFFECTS OF TEMPORARY BALLAST ROADWAYS ON HEATHLAND VEGETATION

1. A series of trials was established to assess the effects of tempora ry roadways on heathland vegetation. These temporary roadways were set up on both dry and wet heath in Dorset (southern England). 2. The roa dways were in place for periods of 2, 4 and 12 weeks in the spring, su mmer and autumn of 1986. 3. The mean height, percentage cover and spec ies composition of the vegetation was recorded before treatment and at the end of each growing season (1986-88). 4. The mortality of rootsto cks and the establishment of seedlings were assessed in October 1987. 5. The results showed that the plots disturbed early in the growing se ason regenerated more rapidly than those disturbed later in the year, and that this trend was continued in subsequent years. 6. No species w as lost or severely reduced as a result of the treatments and changes in the abundance of some species were similar to those changes produce d by standard heathland vegetation management. 7. Ten invasive species were recorded on the plots following treatment; none established in l arge enough numbers to change the original vegetation type.