Deerbrush, known also as bluebrush, mountain-lilac, am! sweetbirch, is a 

 deciduous shrub growing in the mountains from Washington south through 

 California and western Nevada into Arizona. Deerbrush is most commonly 

 found in the ponderosa pine and mixed conifer belts and becomes most abund- 

 ant on the west slopes of the Cascades of Oregon and of the Sierras in Cali- 

 fornia. It typically grows on well-drained, moderately fertile soils, but is 

 common under many other soil conditions. In fact, there is a great variation 

 between the slow-growing and dwarfed individuals of infertile, shallow soil on 

 exposed sites and the unusually large-leaved and fast-growing individuals in 

 moist, fertile soils. The species grows equally well in the open and half-shade, 

 but quickly dies out under dense shade, as when topped by young conifers. 



Reproduction is chiefly by seed, although deerbrush also multiplies by root- 

 stocks after fires or cutting. The seed apparently remains viable for many 

 years, germinating only when favorable conditions develop. Clearing, whether 

 by fire or logging, or both, apparently stimulates germination, as deerbrush 

 often becomes the dominant vegetation following such practices. That is prob- 

 ably why many people believe burning is a logical practice in the management 

 of deerbrush ranges. However, careful study of burns, particularly recurrent 

 burns, has shown that, if forage production benefits, the advantages are only 

 temporary. Burning depreciates forest values, as it destroys timber, water- 

 shed protective cover and soil fertility, recreational facilities, and wildlife. 

 Deerbrush may be the dominant brow.se after a first or second burning, but it 

 rarely survives a third fire. Usually the site deterioration results in the inva- 

 sion of whitethorn (Ceanothus cordulatus) while greenleaf manzanita (Arcto- 

 staphylos patula) sometimes comes in at its upper range. At the lower growth 

 limits whiteleaf manzanita (A. wscida) is a very characteristic associate. 

 Continued burnings almost invariably result in the disappearance of deerbrush 

 and the establishment of dense brush fields of low value. 



Deerbrush is one of the most valuable browse plants of the West, and in 

 California it provides more forage than any other browse species. It is con- 

 sidered good to excellent browse for cattle, sheep, goats, and deer, and fair to 

 good for horses. The palatability of leaves and tender young twigs appears to 

 be increased by their wintergreenlike flavor similar to that of true sweet birch 

 (Betula lento,). This similarity has led to the frequent use of the common 

 name sweetbirch for deerbrush. Ordinarily cattle use deerbrush ranges more 

 efficiently than sheep, because their greater height enables them to obtain more 

 forage from the older and taller stands. 



Deerbrush is so important in the Sierras and southern Cascades that man- 

 agement of many ranges is based on its growth requirements. Deerbrush 

 ranges, for example, are ready for grazing in the spring when the blossoms 

 begin to show. The leaves then are out and the foliage can be partially utilized 

 without apparent injury to the plant. Deerbrush ranges have very high grazing 

 capacities while the plants are young, and produce fat stock. Under average to 

 good growing conditions deerbrush grows rapidly and is often too tall to be 

 browsed when from G to 10 years old. Instead of reseeding, a stand of deer- 

 brush becomes dominated by coniferous trees or some other browse species. 

 Under such conditions deerbrush ranges decline rapidly in grazing capacity. 

 Severe grazing to check the most rapidly growing shrubs in order to maintain 

 the deerbrush stand at a satisfactory grazing height is impractical. Under 

 such management the plants become hedgelike and weaken or even die and the 

 forage yield decreases, while timber reproduction, watershed, and other values 

 are impaired. 



Research at the University of California (see Forest Worker, vol. 7, no. 6, p. 8, 

 November 1981, and Ecology, vol. 13, no. 4, p. 324, October 1932) has shown that 

 with advancing stages toward seed maturity the relative protein and phosphorus 

 content of bluebrush decline and the percentages of calcium, nitrogen-free 

 extract and fats increase. These chemical changes appear to be closely corre- 

 lated with the palatability and nutritiousness of deerbrush browse, which tend 

 to decline as the seed matures. August 2-21 was found to be the period on the 

 Tahoe National Forest when cattle tend to leave deerbrush and also when the 

 calcium content of the herbage markedly increased. 



Deerbrush is typically a loose and slender branched shrub 4 to 12 feet high. 

 The sweet-scented flowers are borne in showy 2- to 6-inch long terminal clusters 

 from April to July (chiefly May and June). 



