California Agriculture, March-April 2001
Volume 55, Number 2
In increasing numbers: Grandparents become parents again
peer-reviewed research articles
Grandchildren raised by grandparents a troubling trend
by Mary L. Blackburn
This study was conducted in response to requests for demographic and needs data on children living with grandparents in California and elsewhere. The 1990 U.S. Census reported that in California, at least 493,080 children under age 18 (6.4%) lived in households headed by their grandparents. In Alameda County, for example, 22,783 children lived with their grandparents and, of these, about 9,330 (41%) were under 6 years old. Grandparents raising their grandchildren is not a new phenomenon, but the conditions under which some assume primary parenting responsibilities are a growing concern. Custodial grandparents may have multiple health problems and experience severe stress when confronted by the attendant costs and responsibilities. The grandchildren often have emotional, learning and physical disabilities, and many live in poverty. This study describes the demographic distribution of grandchildren living in grandparent households in California, standardizes prevalence rates by county and sets priorities for health and human service needs of grandparents and the grandchildren under their care. We recommend program planning within UC Cooperative Extension to respond to the educational and training needs of older caregivers.
Live oak saplings survive prescribed fire and sprout
by William D. Tietje , Justin K. Vreeland , William H. Weitkamp
Sapling surveys conducted before and after a prescribed fire in an oak woodland revealed that approximately half of marked blue oak and coast live oak saplings were top-killed (aboveground tissue of sapling killed) by the fire. Most top-killed saplings sprouted, and sprout growth was strong within one growing season. Light-intensity prescribed fires probably have little effect on overall sapling survival and recruitment, and may benefit individual saplings by reducing competition and recycling nutrients.
Brush piles and mesh cages protect blue oak seedlings from animals
by William H. Weitkamp , William D. Tietje , Justin K. Vreeland
Oak tree branches piled over acorn-seeded blue oaks were tested as protection against cattle and deer. The piles remained in place and apparently free of cattle and deer for 8.5 years, until a wildfire destroyed the branches. Before the fire in 1996, seedlings in the brush had similar survival rates but grew significantly faster than seedlings with no brush. Seedling survival and growth rates declined sharply after the fire, although the surviving trees regained their prefire heights in 3 years. Cages made of aluminum window screening, as protection from small animals, significantly increased seedling survival and growth rates. Growth rates over the 12 years of the trial averaged only about 0.5 to 1 inch per year.
Internal parasites prevalent in California's beef cattle
by Daniel J. Drake , Edward R. Atwill , Ralph Phillips , Eileen Johnson
Sixty percent of cattle not dewormed within 4 months of sampling were shedding parasite eggs or larva. The prevalence of shedding varied greatly for different types of internal parasites. Prevalence of shedding for major Strongylate nematodes was 54%; thread-necked intestinal nematodes, 6%; lungworms, 0.8%; coccidia, 18.1%; and tapeworms, 2.1%. Anthelmintic (deworming) treatments lowered prevalence compared to untreated cattle, but the major Strongylate nematodes and coccidia were still sufficiently prevalent that the resulting pasture contamination would restrict the potential success of control programs.
Potential economic impacts of irrigation-water reductions estimated for Sacramento Valley
by Hyunok Lee , Daniel Sumner , Richard Howtt
In the Sacramento Valley, irrigation water is vital to agriculture and agriculture is vital to local economies. This study investigates these relationships by asking: If surface irrigation water were cut by 25%, what would be the economic impacts on farmers and on communities? The study results indicate that the effects would not be uniform across crops and the eight counties in the Sacramento Valley. In most regions and for most crops, a cut in irrigation water would cause a modest acreage reduction of up to 3%. Overall crop-revenue losses for core regions would total $8 million while the loss for the entire Sacramento Valley would be $11 million. About 80% of those losses would take place in poorer counties that depend most heavily on agriculture, and particularly on rice. However, in response to surface-water reductions, farmers and others would mitigate their losses by making adjustments such as conserving water, changing cropping patterns or implementing new technologies.
editorial, news, letters & science briefs
Human Resources equipped to serve a dynamic California
by Karen Varcoe
From our readers
Center proposes solution for ag biotech licensing disputes
by Janet Byron
Exotic pest research goes high-tech
Grandparents raising grandchildren a national concern
by Janet Byron