2015-07-15_REPORT - M1988044 - Laserfiche WebLink

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measures can be implemented to reduce the soil loss while still allowing the water to run where it wants to run. 4. Revegetadon - Approximately 32 acres of land was seeded with the designated seed mixture last year. Seeding was done by drilling and was performed in mid-June. Soil moisture at the time of seeding was good and with all the moisture received in May and earlier, the soil was moist to considerable depth. If the moisture had not been so good, seeding would have likely been delayed until late August. A check of the revegetation in March 2015 showed excellent survival of the planted species over the winter and a moderate amount of young annual species invading. Nothing particularly worrisome, but about what was expected. The grazing lessee, in an onsite discussion, indicated they would be grazing the reclamation area a small amount. Although that was a concern to the author of this report as a result of past experiences with grazing new reclamation, it appeared the lessee would only do very limited grazing. The inspection on July 2 showed that the grazing was limited and any fears of a disaster were done away with. The excellent management is greatly appreciated. The vegetation was still in excellent condition even though it is obvious that some grazing had occurred. A little grazing is not a bad thing as it encourages tillering of the grasses to increase cover that reduces erosion. It is a delicate balance with new growth though and no damage has occurred as a result of the grazing. In fact, it was probably much more beneficial than detrimental. However, in the July inspection something very unusual was immediately noted. Other than a moderate and small amount of cheatgrass which can hardly be avoided on the Lowry Range, the "weedy" annual species were almost totally absent from the area. Not a single tumbleweed was found in the areas inspected. There probably are a few, but none were seen. That is extremely significant in light of what has happened in the past with prodigious tumbleweed growth in the first year followed by virtual disappearance by the fourth year. That is the normal pattern. But that is not occurring here. The perennial species are doing very well and growing, well, like weeds. There are two possible explanations for this. First is the possibility that the cattle grazing occurred at the ideal time when tumbleweeds are palatable and the cattle ate them all. Based on the pattern of grazed grasses that does not seem likely unless the cattle ignored the grass and ate only the annuals. That does not seem likely. In fact, it seems highly improbable considering the size of the area involved. There should still be prominent tumbleweed growth here and there, but there isn't. The other possible explanation involves nitrogen nutrition in the stockpiled and subsequently spread soil. It is well known that in rich nitrogen soils weed growth is always vigorous and prolonged, sometimes spanning decades of annual species dominance or at least prominence. But soils with moderately low to moderate amounts of available nitrogen tend to produce only limited amounts of annual species growth that rather quickly disappears. That is also accompanied with strong native perennial growth which, of course, is what is desired. Weeds like tumbleweed love nitrogen and the more the better. Many native grass and forb species have low nitrogen requirements and some are fairly capable nitrogen fixers that are adversely affected if grown in high nitrogen containing soils. Because much of the soil that was placed on this area was stockpiled for a long time and with that long period in deep stockpiles it is possible that plant available nitrogen declined to a low level but not so low Status report for 2015 due July 15, 2015 Page 6 of 10