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This article reports results of trials with mechanical rumen stimulators…Rumen Ruticulators…in lactating dairy cows. Results reported here indicate that these rumen stimulators have no effect on feed intake or milk fat production in dairy cows.

While working on scale tip rot of lilies, it was discovered that the same bacterium, Pseudonwnas, might also be the cause of scorch disease of rhizomatous iris. Bacteria isolated from scorch-diseased iris that looked like the lily Pseudomonas were inoculated to bulb scales of Easter lily with positive results and the original bacterium was reisolated from the lily scales.

Natural FIRE is recognized by the National Park Service as one of the ecological factors contributing to the perpetuation of plants and animals in a given habitat. As such, fires in national parks resulting from natural causes may be allowed to run their course under specified condition^. Prescribed fire may be used as a substitute for natural fire where this can achieve approved vegetation or wildlife management objectives. To provide the facts upon which to base such a program, researchers at Sequoia and Kings Canyon National Parks are studying the role of fire in various plant communities; of greatest interest at this time are forests of the giant sequoia-mixed conifer type.

Preliminary shaking tests in 1970 for citrus harvesting in Ventura County did not produce the desired percentage of fruit removal without damage to fruit or foliage. There was excessive damage to mature navel oranges during removal, and also damage to small green Valencia oranges, grapefruit, and lemons that would have matured into the next season's crop. However, separation of mature fruit from the stem was acceptable for all varieties. Further equipment modifications and abscission chemicals will be necessary to provide efficient harvesting of more mature, good quality fruit with less damage to the immature fruit that should remain on the tree. Research is continuing with growth regulators to find a successful abscission-producing material that would loosen the mature fruit…with minimum peel damage…as an aid to shake-harvesting. Successful commercial abscission trials using cycloheximide on oranges have recently been reported in Florida.

THE RESIDUAL CHARACTERISTICS of common herbicides in California have been studied for over seven years at various locations throughout California from Tulelake in the north to El Centro in the south. The many differences in crops, soils and climates, cause great differences in the length of time soil-applied chemicals remain active.