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Eight Alpine wethers (8-9 months of age, 27.5+/-1.10kg body weight (BW)) were randomly assigned to consume, free-choice, either shining sumac (Rhus copallina) or water oak (Quercus nigra) leaves as a sole diet. Leaves were collected and dried prior to feeding. A 14-day adaptation period was followed by a 4-day total fecal and urine collection. Chemical composition (%) of the fed water oak and shining sumac leaves revealed similar levels of OM (95.9 and 94.1) and N (1.54 and 1.42) but higher concentrations of cell wall fractions, NDF (54.8 and 31.2) and ADF (34.5 and 26.4), in water oak than shining sumac. Body weight of wethers differed between treatments, although this was not reflected in DM intake. Average daily intake values were 616g DM, 589g OM and 9.3g N. NDF intake was significantly lower (P=0.002) in goats-fed shining sumac than in those that consumed water oak (192 versus 330g). Daily fecal output of all components was higher (P

The pergid sawfly Heteroperreyia hubrichi from Brazil was screened under quarantine to determine its safety as a biological control agent of the exotic invader Brazilian peppertree, Schinus terebinthifolius (Anacardiaceae). No-choice host-specificity tests were conducted using 36 plant species in 15 families. Neonate larvae of the sawfly were exposed to the plants in a quarantine facility and in field trials in Florida and Brazil, respectively. The neonate larvae fed and completed their development to the adult stage only on Brazilian peppertree and cashew Anacardium occidentale L. Although the sawfly larvae were able to feed and reach the pupal stage on cashew in Brazil, the adult female was not able to oviposit on this plant and oviposited only on Brazilian peppertree. The first instars fed slightly, consuming less than 5% ( 2 ) of the foliage on 3 plant species (mango, Mangifera indica L.; poison oak, Toxicodendron toxicarium (Salisb.) Gillis; Surinam cherry, Eugenia uniflora L) and moderately between 5 to 10% (1–2 cm 2 ) on 4 species (California peppertree, Schinus molle L.; Chinese pistachio, Pistacia chinensis Bunge; poison sumac, Toxicodendron vernix (L.) Kuntze; winged sumac, Rhus copallina L). This injury was made by 10 larvae, so individual feeding was not significant and all larvae died without reaching the pupal stage. These results indicate that H. hubrichi is highly specific to the Brazilian peppertree. A request for the release of this insect in Florida, submitted in October 1996, was approved by the Technical Advisory Group on the Introduction of Biological Control Agents of Weeds (TAG) and is currently under a risk assessment by the USDA-APHIS.