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the sites. However, unneeded plots were not included <br />in the study. <br />Seeded greases provided greater cover than natural <br />regeneration in a burned area in Oregon (Anderson <br />and Brooke 1975). Litter and mulch also developed <br />more rapidly on the seeded sites. After 4 years, how- <br />ever, all sites had more than 70 percent ground cover. <br />Legume species included in the seeding mix for <br />wildlife forage generallydidnot survive. Seededgrassea <br />appeared to suppress growth of native shrubs and <br />annual forbs, particularly in the second and third <br />year after fire. Erosion amounted to only 6 t ac ' <br />(5.6 Mg ha 1) during the first 2 years after fire on <br />seeded sites. The unneeded site was not measured but <br />also appeared to experience little erosion (Anderson <br />and Brooks 1975). <br />In contrast, Dyrnesa (1976) measured negligible <br />cover produced by seeded species on severely burned <br />plots in Oregon. Total vegetation cover was only 40 <br />percent after 2 years even on lightly burned sites. He <br />suggested that nitrogen fertilization might have im- <br />proved vegetation growth. Earlier work by Dyrnese <br />(1974) found that grass vigor decreased 4 years after <br />seeding along forest roads for erosion control, and <br />refertilizationinyear7reinvigoratedperennialgraasea <br />in the plots. On disturbed firelinea, HIock and others <br />(1975) seeded various grasses and legumes and <br />found that fertilization greatly increased initial covei <br />of most ap~ecies tested. Fertilization with 45 lb ac <br />(50kgha )drilledureasignificantlyincreasednative <br />plant regrowth, but not production of seeded species, <br />on granitic soil in Idaho (Cline and Brooks 1979). <br />Seeding and fertilizer treatments were compared on <br />separate watersheds in the Washington Cascades <br />after a fire swept through the Entiat Experimental <br />Forest (Tiedemann andHIock 1973). Seedingincreased <br />plant cover at the end of the fast growing season by <br />about one third, from 5.6 percent on the unneeded <br />watershed to 7. b to 10.8 percent on the seeded water- <br />eheda. Seeded graeees made up 18 to 32 percent oftotal <br />cover on seeded sites. Nitrate concentration in streams <br />increased immediately after fertilizer application, but <br />subsequently fertilized and unfertilized watersheds <br />had similar stream nitrogen dynamite (Tiedemann <br />and others 1978). Later that summer, record rainfall <br />events caused massive flooding and debris torrents <br />from treated and untreated watersheds alike (Helvey <br />197b).Inthesecondyearafterfire,averagetotalplant <br />cover increased to 16.2 percent on the unneeded water- <br />shedand 16.4 to 23 percent on the seeded watersheds. <br />Seeded grasses comprised about 7 percent cover on <br />seeded watersheds (Tiedemann and Klock 1976). On <br />south-facing slopea,the unneeded watershed had as <br />much or more cover than the seeded ones. Although <br />fertilization did not affect plant cover either year, <br />Tiedemann and HIock (1976) felt that it increased <br />seeded grass vigor and height. <br />From an erosion standpoint during the first winter <br />after fire, the amount of seeded grass present at the <br />time major storms occur is more important than the <br />amount present at the end of the growing season, <br />when it ie usually assessed in studies. In southern <br />Oregon, annual ryegrass seeding and fertilization <br />did not significantly increase plant cover or reduce <br />eroaionby early December, when that winter's major <br />storms occurred (Amaranthus 1989). The seeded and <br />Fertilized plots had significantly less bare ground <br />than the unneeded plots. Erosion was low and not <br />significantly different between treatments, though it <br />trendedlowerontheseededplots.Amaranthua(1989) <br />pointed out that timing of rainfall is critical to both <br />grass establishment and erosion, and that different <br />rainfall patterns could have produced different re- <br />sults from the study. <br />In contrast, grass seeding plus fertilizer did not <br />significantly increase total plant cover during the first <br />5 years after a northern Sierra Nevada fire (Roby <br />1989). Seeded grass cover did not exceed 10 percent <br />until3years atterthefire,whentotalcoveronunseeded <br />plots was greater than 50 percent. There was no <br />difference in eroaionbetween the seeded and unneeded <br />watersheds during the first 2 years after fire. Roby <br />(1989) concluded that grass seeding was ineffective as <br />a ground cover protection measure in that location. <br />Geier-Hayes (1997) also found that total plant cover <br />did not differ between seeded and unneeded plots for <br />5 years after an Idaho fire. Seeded plots had lower <br />cover of native epeciea. Erosion was not measured. <br />Several epeciea commonly used for poatfire seeding, <br />because of their rapid growth and wide adaptability <br />(HIockandothers 1975),havebeenfoundtobentrongly <br />competitive with conifer seedlings in experimental <br />plots. Orehardgrasa (Dactyiis glomerate), perennial <br />ryegrass (Lo]ium persona), and timothy (Phleum <br />pretense) reduced growth of ponderosa pine seedlings <br />in teats conducted in California (Baron 1962). <br />Orchardgrass and created wheatgrasa (Agrapyron de- <br />sertorum) reduced ponderosa pine growth in Arizona <br />(Elliot and White 1987). Field studies on aerial <br />seeded sites in California found low pine seedling <br />densities on most plots with annual ryegrasa cover <br />higher than 40 percent (Conard and others 1991, <br />Griffin 1982). <br />Amaranthus and others (1993) reports d significantly <br />lower survival of planted sugar pine (Pious Iam- <br />bettiana) seedlings in plots heavily seeded with an- <br />nual ryegrasa than in unneeded eontrole during the <br />first pontfire year in southern Oregon. Soil moisture <br />was significantly lower and pine seedlings showed <br />significantly greater water stress in the seeded plots. <br />Ryegrasa cover was 49 percent when tree seedlings <br />were planted and 85 percent by midsummer, while <br />total plant cover was only 24 percent at mid-summer <br />on the control plots. The next summer, a second group <br />18 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-x3.2000 <br />