The defoliation of the eastern white pine (Pinus strobus) across the northeastern United States is an escalating concern threatening the ecological health of northern forests and economic vitality of the region's lumber industry. First documented in the spring of 2010 affecting 24 328 hectares in the state of Maine, white pine needle damage (WPND) has continued to spread and is now well established in all New England states. While causal agents of WPND are known, current research is lacking in both sampling distribution and the specific environmental factor(s) that affect the development and spread of this disease complex. This study aims to construct a more detailed distribution map of the four primary causal agents within the region, as well as utilize long-term WPND monitoring plots and data collected from land-based weather stations to develop a climatic model to predict the severity of defoliation events in the proceeding year. Sampling results showed a greater distribution of WPND than previously reported. WPND was generally found in forest stands that compromised >50% eastern white pine by basal area. No single species, nor a specific combination of species had a dominating presence in particular states or regions, thus supporting the disease complex theory that WPND is neither caused by an individual species nor by a specific combination of species. In addition, regional weather data confirmed the trend of increasing temperature and precipitation observed in this region with the previous year's May, June, and July rainfall being the best predictor of defoliation events in the following year. Climatic models were developed to aid land managers in predicting disease severity and accordingly adjust their management decisions. Our results clearly demonstrate the role changing climate patterns have on the health of eastern white pine in the northeastern United States.
The disease complex white pine needle damage (WPND), first reported in 2006, has now escalated to an epidemic state across the northeastern United States. Although this complex is composed of several fungal species, Lecanosticta acicola is considered to be the primary causal agent. Knowledge regarding the epidemiology, specific climatic factors that affect the spread of L. acicola on eastern white pine (Pinus strobus) in natural forest settings, and potential risks repeated defoliation may have on tree health is limited. Therefore, this study examined how climatic variables affect the abundance and distance of spore dispersal of L. acicola and compared litterfall caused by defoliation versus natural needle abscission. Conidia were observed on spore traps from May through August, with a peak in abundance occurring in June, corresponding to the defoliation of second- and third-year foliage measured in litter traps. During peak spore production, relative humidity and the occurrence of rainfall was found to have the greatest influence on spore abundance. Our results will aid managers in determining how far from infected trees natural regeneration will likely be affected and predicting future disease severity based on climatic conditions.
The 1999 National Market Cow and Bull Beef Quality Audit comprised face-to-face interviews with industry representatives (n = 49); in-plant evaluations of cattle in holding pens (n = 3,969), carcasses on harvest floors (n = 5,679), and in carcass coolers (n = 4,378); and a strategy workshop. Face-to-face interviews suggested that the beef industry was most frequently concerned about the presence of antibiotic residues in carcasses, presence of lead shot in carcasses, and price discovery for carcasses following excessive trimming of bruises and testing due to arthritic joints, pathogens, or antibiotic residues. Although live animal evaluations determined that 73.4% of beef cows, 60.8% of dairy cows, 63.7% of beef bulls, and 70.9% of dairy bulls did not exhibit evidence of lameness, losses due to lameness were greater (P < 0.05) than in the 1994 National Non-Fed Beef Quality Audit. In-plant audits revealed that 88.9, 10.3, and 88.2% of cow carcasses and 18.9, 21.2, and 52.9% of bull carcasses had inadequate muscling, arthritic joints, and at least 1 bruise, respectively, all of which resulted in greater (P < 0.05) losses than the same defects in 1994. Audits revealed that 88.9% of cow carcasses and 18.9% of bull carcasses were lightly muscled, resulting in greater (P < 0.05) losses for cow carcasses, and similar (P > 0.05) losses for bull carcasses, than the same defect in the 1994 audit. Also, 14.5 and 30.8% of cow carcasses and 6.9 and 5.9% of bull carcasses had excess external fat and yellow-colored external fat, respectively, which was an improvement (P < 0.05) over 1994 results. In aggregate, 24.1, 19.2, 7.2, 6.7, 9.5, and 1.1% of livers, tripe, hearts, heads, tongues, and whole cattle or carcasses, respectively, were condemned and 60.6, 2.4, and 46.5% of cattle had hide damage from latent defects, insect damage, and brands, respectively. Condemnation rates were generally lower (P < 0.05), but tongue condemnations and frequency of branded hides were higher (P < 0.05) than in 1994. Producers should promote value in cows and bulls by managing to minimize quality defects, monitoring health and condition, and marketing in a timely manner. Using these techniques, producers might have recaptured $13.82, $27.50, and $27.50, respectively, for each cow or bull harvested in 1999.
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