TURFCOMMS V. 7, 1.7 f Feb. 19, *94 PURPOSE: To pass on what we learn willingly and happily to others in the profession so as to improve turf conditions around the country. Texas Turf Conference (continued): I have two talks on fungicide use that I plan to go to press with soon as a single issue. The talk below is just the last talk on the program that I took notes on. The last talk I have notes on is that given by Carl Rygg, supt. of Squaw Creek, Olympic Valley, CA. His resort golf course is up in the Lake Tahoe area at 6200 feet of elevation. Due to environmental concerns the only way they could get a golf course built was to promise to use no pesticides (that means, no insecticides, herbicides, fungicides, etc.). Now at that elevation insects are seldom a problem and weeds are not too much of a problem but snow mold will eat you up! With 10 foot of snow in the winter of 1992-3 it cost them $50,000 for snow removal on bentgrass greens and tees. The pictures of snowmold damage were as bad as I've seen. His approach is to go in and reseed as soon as feasible in the spring. Seeing that most play isn't till after the first of June, he does have some time for recovery. Another rule he has to abide by is no fertilizer may be applied until soil temperature reaches 45°F, which is usually mid-May and he can not apply more that 1/4 lb.N/M/application and the applications must be at least two weeks apart IS THIS A SIGN OF THINGS TO COME? GRASSES REDUCE TREE GROWTH: IVe been trying to convince students and clients the truth of this for many years. Most superintendents have no trouble understanding the reverse: Trees reduce grass growth. New research published in the J. Amer. Soc. Hort. Sci. Vol. 118, pg. 714, 1993 sheds some new light on the interference of grasses on tree root growth. The article is titled "Orchard Floor Management Affects Peach Rooting". It is written by three members of the Mich. St. U. Dept. of Hort. They did research comparing six different types of orchard floor management. Two types of vegetation-free management: one with herbicide and one with culti-vation and four with vegetation. The turf species used were 'Park' Kentucky bluegrass, 'Wintergreen' chewings fescue, and (K-31) tall fescue. Alfalfa was used as the fourth species. "Trees maintained vegetation-free with herbicide had the most roots. Trees in the vegetation-free plots, maintained with herbicide or cultivation, produced more roots 1.2 m [4 feet] from the tree than trees in the vegetative covers. The number of roots, 1.2 m from the tree, was lowest in the tall fescue treatment." TURFCOMMS is published at unpredictable intervals by the editor and publisher: Douglas T. Hawes, Ph.D. 2408 Roundrock Trail Certified Professional Agronomist Piano, Texas 75075 Specializing in Golf Course (214) 867-0176 Maintenance Consulting Subscription cost is $15. Send checks to Doug Hawes at the above address Again let me say using herbicides to control the vegetation around newly planted trees is a good way to get the most out of your investment in new trees. This data appears to indicate that tall fescue around the tree is more restrictive of tree root growth than Kentucky bluegrass. TREES FOR THE SOUTHERN GREAT PLAINS: This is the title for a very informative and somewhat surprising article that appeared in theOct./Dec. 1993, issue of HortTechnology. It is written by Doxon and Kirksey of New Mexico State Univ. and tells of studies begun in 1923, at their Tucumcaii N.M. location. This is a hardiness zone 6B site which experienced highs up to 108F (1939 and 1957) and a low of -22F, the latter in 1957. Hardiness zone 6B runs across the panhandles of TX and OK, through northern Arkansas, southern Pennsylvania and NYC. Rainfall in Tucumcari averages 16 inches and during the study ranged from 6 inches in 1934 to 35 inches in 1941, definitely semi-arid. Large-scale tree plantings were made in 1923, 1931 and 1938. The recommendations that the authors make were arrived at based on survival of trees until 1987. The trees were not irrigated, in fact had receive no maintenance from 1949 to 1987. "Only three deciduous species had good survival rates over the 64 years of the study." These were GAilcpsh Uneausy SKiztpAa* JU/U/KL, and ^Jtf8.0). Scientist have been unable to come up with a clear chemical structure and have now decided that the reason humus is so stable is the fact that it has a random structure thus no microbial enzyme system can effectively break it down (see the text above). If you have new greens with low cation exchange capacity or situations in which you need greater root systems or you are having trouble with iron absorption with any plant you should conside this product might be helpful. For more information about Humate call 1-800-393-4769. I suggest you spray on their liquid concentrate. Be careful on bentgrass greens under heat stress. END