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Introduced, alien annual grass and forb species evolved during thousands of years of heavy grazing and periodic drought in southern Europe, and thus have many adaptations to compete successfully against the native perennials under present grassland conditions in California. Menke suggests to restore native prairie in California, strategies are needed to reduce the competitive edge of alien species. Menke reviewed research done on grasslands and concluded that management of native perennial grasses requires strategic application of grazing and fire to accomplish the goal of restoration. He notes that restoration treatments must: a) enhance the vigor of mature perennial grasses, thereby increasing their longevity; b) promote clonal fragmentation of decadent, over-mature plants into multiple, vigorous daughter plants; and c) encourage native grass seed production and increased seedling establishment success. One treatment is time-controlled, short-duration, high intensity sheep or cattle grazing for several days in early spring. This removes substantial amounts of alien annual plant seed while it is still in inflorescences and opens up the sward canopy to allow light to penetrate to young, short-statured seedling perennials. Summer high-intensity grazing is another alternative but it does not reap the added benefit of alien annual plant seed removal like that of spring grazing, therefore it is a second choice alternative. Studies have shown that prescribed late spring burning reduces alien annual plant seed production, and the resulting size of the seedbank, and increases perennial grass seedling establishment due to litter removal and lowered competition. However, the effect is gone by the second or third year after a fire. Meneke concludes that while more costly artificial reseeding and other plant establishment procedures are possible, prescribed burning and grazing are useful tools to restore or maintain the abundance of native perennial grasses.