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28 1 30x30 cm quadrats. Two locations along the transect with successful seedling " establishment were selected and a 10 cm deep hole was dug at each. Soil samples were collected from each of the visibly distinct horizons exposed. Similarly, one or two locations with no seedlings present were excavated and soil samples were collected. At Mather's Hole, no bare areas of sufficient size were found for sampling and only one soil sample was collected from the transect. The samples were returned to the University of New Mexico, oven-dried at 105 C for 24 hours, weighed, and dry-sieved through the following series of standard soil sieves: Nos. 10, 18, 35, 60, 120,- and 230 (the numbers indicate the number of grids per inch of sieve surface). The sieving separated the sample into seven textural classes: gravel, five divisions of sand (f ran very coarse to very fine), and fine (which included both silt- and clay-sized particles). Some samples with a high clay content formed aggregates which did not break apartin the sieving process. These will cause an exaggeration of coarse particle sizes and an under-estimation of the fines. Sieve contents were inspected for aggregates and their presence was recorded. Percentage composition of the seven particle size classes was calculated for each horizon s amp led. Tamarisk Ages Two sites were selected on the Green River in Lodore Canyon for cutting and aging tamarisk stands. The first was a gravel island between Trailer Draw and Buster Basin (mile 238.5) and the second was a gravel bar across and downstream from Wild Mountain Campground (mile 229.3). A total of twelve plants were cut. The criteria for cutting were: (1) the plant should have a distinct central trunk with no branching or spouting evident below six inches in height, (2) there must be some living foliage present above the trunk and (3) the diameter