Dan M. Harman

First record of the larch sawflyPristiphora erichsonii in Maryland, with notes on its distribution

The larch sawflyPristiphora erichsonii (Hartig) has not been previously reported in Maryland. In 1966 it was observed at 11 locations in the counties of Garrett, Allegany, and Washington in Western Maryland. Its easternmost point of occurrence was Fort Frederick State Park in Washington County. Larch stands east of this area that were examined in 1966 were not infested. In preliminary studies the following insect parasites were recovered from larch sawfly cocoons in Garrett County:Tritneptis klugii (Ratzeburg),Mesoleius tenthredinis Morley,Euceros sp.,Aptesis sp.

Site Quality in Relation to Damage by Locust Borer, Megacyllene robiniae Forster in Black Locust

Forty-three study sites within eight counties in Maryland were utilized in an investigation of Site Index in relation to attack by the locust borer, Megacyllene robiniae (Forster), on the black locus tree, Robinia pseudoacacia L. In addition, several other factors related to borer attack intensity were tested for relationship with Site Index of black locust. Site Index was found to be negatively correlated with borer tunnels per tree, i.e., sites with higher Site Indices had statistically fewer borer attacks per tree. Positive correlation was also inferred between Site Index, borer attacks, and (1) scarring from previous years borer attacks, (2) herbaceous biomass within-site, (3) elevation above sea level, (4) soil factors, including pH, %sand, silt, and clay.

Feeding habits of the larch sawfly larvae,Pristiphora erichsonii (Hymenoptera: Tenthredinidae) on Japanese larch in Maryland

Studies on the feeding habits of larch sawfly larvae,Pristiphora erichsonii (Hartig), in Maryland, substantiated previous reports of a feeding preference for spur foliage over elongated shoot foliage. In field examinations on 20 infested Japanese larch trees, significantly greater quantities of foliage were consumed from spurs than from elongated shoots. However, elongated shoots constituted about 1/4 of the total foliage weight consumed. Larvae reared in the laboratory on a constant diet of elongated shoots were more restless, consumed less foliage, and incurred higher mortality than larvae reared on spur foliage. In chemical comparisons, spurs tested quantitatively higher in carbohydrates, proteins, resin, pitch, tar, and photosynthetic pigments than elongated shoots.

Parasites of the nantucket pine tip moth,Rhyacionia frustrana on three pine species in Maryland

Studies of the insect parasites of the Nantucket pine tip moth were conducted on loblolly, Scotch, and Virginia pine in Maryland. Twenty-five species of parasites and associated species were reared from infested stems, 5 of which had not previously been reared from the Nantucket pine tip moth. Total percentages of parasitism was highest for loblolly pine, and lowest in Scotch pine, although the greatest number of parasite species were represented in the Scotch pine material. The parasite species most commonly encountered in the study wasEurytoma pini Bughee.

Occurrence of the porcupineErethizon dorsatum and the nutriaMyocastor coypus bonariensis in Western Maryland

The porcupineErethizon dorsatum (L.) has been taken recently by hunters at one location in Allegany County and two in Garrett County, Maryland. Except for fossil records, the porcupine has been unreported in Maryland since 1881. The nutriaMyocastor coypus bonariensis (E. Geoffroy St.-Hilaire), of uncertain status in western Maryland, was trapped in two locations in Garrett County. Possible sources of the nutria are farms where the animal is being reared for furs.

Frequency and Distribution of the American Dog Tick on the Nutria in Maryland

Infestation by the American dog tick Dermacentor variabilis (Say) on nutria Myocastor coypus Molina was studied in marsh habitat on Blackwater National Wildlife Refuge, Maryland. Ticks attached to ears of nutria during the spring and summer months, with peak infestation occurring in May. The prevalence of tick infestation overall was low. Neither sex of host or body size was significantly correlated to tick intensity. Intensity of infestation varied from 1-40, with most infested individuals harbor-

Managerial applications of a 4‐year regional program in remote sensing

A study was conducted to determine the degree of regional utilization of remote sensing data from the NASA Wallops four‐year old Chesapeake Bay Ecological Program. Forty‐three managerial agencies utilized the data in more than 80 projects related to regional management. User and project emphases were categorized on a primary and secondary basis. The results of the study indicate that remote sensing is being practically applied to the accomplishment of a diverse variety of managerial objectives by a significant proportion of the public agencies of the middle‐Atlantic states.

Leader and bark characteristics in different growth categories of White Pine (Pinus strobus L. and Pinus monticola Dougl.) in Maryland

Dimensional and chemical aspects of leaders and bark were investigated in tall (40–75 ft) eastern white pines (Pinus strobus) and in smaller (12–25 ft) trees growing in the open and in shade. Leaders from young open grown trees were longer, of greater diameter, and had thicker bark than leaders from tall white pines and from young shaded white pines. Tall trees were intermediate between the open grown and shaded trees in leader length and diameter but had the thinnest bark. Bark thickness in similar aged portions of laterals increased progressively at higher vertical levels in the trees. In spectrophotometer tests, light transmittance was higher for shoots than for bark from lateral branches and the main stem in both eastern white pine and western white pine (Pinus monticola).

Natural mortality of feeding and cocooning stages of the larch sawflyPristiphora erichsonii in Maryland

Studies were conducted to assess natural mortality in larval and cocoon stages of the larch sawflyPristiphora erichsonii (Htg.) in Maryland. Among newly-cocooned prepupae in August, mortality from unknown causes averaged 23.39%, whereas mortality definitely assessable to parasitism averaged 0.73%. Numbers of larvae missing from 100 colonies during the feeding stage averaged 9.25% of the total. The following 4 species of parasites were reared from the larch sawfly in Maryland;Tritneptis klugii (Ratz.),Mesoleius tenthredinis Morl.,Eucerus sp., andAptesis sp.

White-pine Weevil Attack on Naturally Seeded Virginia Pine in a Severely Attacked White Pine Plantation'

Attacks by the white-pine weevil were observed on Virginia pine,Pinus virginiana, a species not previously reported as a host of the weevil. In a heavily infested white pine plantation, 15.2% of the naturally seeded Virginia pines were attacked. However, only 13.6% of the attacked trees supported successful broods which resulted in emergence of new adults from the stem. The remaining 86.4% of the broods were unsuccessful.