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32 .weed seeds. On the experimental plots the broadleaf annual weeds were controlled by a spray application of Bromoxynil at the rate of 1/4-pound per acre on 7 July. This herbicide is selective for broadleaf plants and will not affect grass seedlings (2,4-D will affect small grass seedlings). The Bromoxynil damaged the weeds but did not kill them so on 13 July the plots were resprayed with Bromoxynil at the rate of 1 pound per acre. This application killed all the weeds except pigweed. The pigweed was later hand pulled on the plots, but in a large scale operation, it probably would be sprayed with 2,9-D after the grasses have reached a non- susceptible 4-leaf stage. The plots were sprayed with malathion for control of an abundant leafhopper population on 14 July. The entire range (several sections) was sprayed for grasshopper control in late July (probably with Sevin). On extensive revegetation projects a close watch should be maintaine3 for major insect problems during the year of establishment and control measures taken if needed. Depth of Sand over Clay For reclamation it will be expensive to move quantities of sandy topsoil and subsoil for placement over spoil which will largely be clayey shales from the overburden above the coal. We need to know the depth of sand needed above the clay to sustain the native plants adapted to the sand. The problem is critical because the depth of sand must be enough to prevent water logging, and winterkill. On the other hand, clay under a reasonable depth of sand may hold water and fertility for greater production than can be obtained on the existing deep sand. To investigate this plots were put in with different depths of sand over clay shale. The treatments were: 1 foot of sand topsoil over clay shale feet of sand (1 foot of topsoil over 1 foot of sub- soil) over clay shale. . 3 feet of sand (1 foot of topsoil over 2 feet of sub- soil) over clay shale. ~, : .