Morphological and phylogenetic analyses reveal a new genus and two new species of Tubakiaceae from China

Species of Tubakiaceae have often been reported as plant pathogens or endophytes, commonly isolated from a wide range of plant hosts. The isolated fungi were studied through a complete examination, based on multilocus phylogenies from combined datasets of ITS/LSU/rpb2 and ITS/tef1/tub2, in conjunction with morphological characteristics. Five strains isolated from Lithocarpus fohaiensis and Quercus palustris in China represented a new genus of Tubakiaceae, Obovoideisporodochium and three species, viz. Obovoideisporodochium lithocarpi sp. nov., Tubakia lushanensis sp. nov. and T. dryinoides.

The Arboricultural and Economic Benefits of Formative Pruning Street Trees

Research was undertaken to determine the need for, and costs of, formative pruning recently planted street trees. Specimens of Corymbia citriodora (48), Platanus × acerifolia (104), Pyrus calleryana (79), Quercus palustris (65), and Ulmus parvifolia (52) were surveyed. Health was similar for all species, but form and structure varied. Data showed that codominant stems (68%) and included bark (40%) in the canopy or trunk were by far the most common structural defects. Codominant stems were reported in 92% of all Ulmus parvifolia, 66% of Quercus palustris, 61% of Pyrus calleryana, 44% of Platanus × acerifolia, and 19% of Corymbia citriodora. The number of trees of a species that displayed no structural defects was 25% or less except for Corymbia citriodora with 60% showing no structural defects. The pruning required to rectify these structural defects was recorded and then multiplied by a time factor for pruning with secateurs (hand pruners), a handsaw, or a pole pruner. Total time was then converted to an economic cost using current labor market prices. Platanus × acerifolia required the most work per tree with a final formative pruning cost of AUD $4.13 followed by Ulmus parvifolia ($3.25), Pyrus calleryana ($2.76), Quercus palustris ($1.62), and Corymbia citriodora ($0.99). This compares with an average cost of $44.59 per tree for structural pruning 20 year old trees. Formative pruning makes sound arboricultural and economic sense.

Effects of larval host diameter on body size, adult density, and parasitism of cerambycid beetles

In this study, we assessed the relationship between the size of bolts cut from pin oak trees, Quercus palustris Münchhausen (Fagaceae), and eastern white pines, Pinus strobus Linnaeus (Pinaceae), and the number and body size of cerambycid beetles (Coleoptera: Cerambycidae) that develop within them. From oak bolts emerged adult Graphisurus fasciatus (De Geer) (98% of beetles) and Xylotrechus colonus (Fabricius), while pine bolts produced Monochamus carolinensis (Olivier) (95%) and Astylopsis sexguttata (Say). The number of G. fasciatus was positively correlated with the diameter of the oak bolts, while the greatest number of M. carolinensis emerged from pine bolts of intermediate diameter. Body size of both species was positively correlated with bolt diameter. Rates of parasitism were very low, only 0.9% for oaks, and averaging 5.3 ± 8.6% across pine bolts. Oak bolts yielded the braconid wasps (Hymenoptera: Braconidae) Wroughtonia ferruginea (Brues) and a species in the genus Atanycolus Förster (similar to Atanycoluscharus (Riley)), and an ichneumonid (Hymenoptera: Ichneumonidae) in the genus Demopheles Förster. Pine bolts produced a braconid in the genus Digonogastra Viereck, and the tachinid fly (Diptera: Tachinidae) Billaea monohammi (Townsend).