THE AUD U BOW BU YE eae 
oO 
7. Organize and promote a public education campaign on Dutch elm disease 
to be continued as long as control is necessary. 
8. Having designed a program, present it to local officials and the public 
for approval. 
A Suggested Procedure for Complete Sanitation 
SANITATION is basic to control of Dutch elm disease, and is most effective 
when done on a community-wide basis. 
1. Obtaining specimens from suspected trees for a culture test is necessary 
only to determine if the disease has invaded a new area. 
2. Remove and destroy by burning all trees showing general foliage wilt 
and brown streaking in sapwood. 
Systematically scout the community for the disease in mid-June and 
again in mid-August. Have this done by a person trained in disease de- 
tection and field diagnosis. 
4. Destroy by burning all elm trees considered generally undesirable be- 
cause of: weakness, unsightliness, hazard, poor location, and especially 
those infested with elm bark beetles. 
5. Systematically scout the community on a block-by-block basis for piles 
of elm wood. This wood must be destroyed. 
6. Prune and destroy weak, dying or dead wood from all elm trees in the 
community. 
7. Mark for observation non-diseased trees in which bark beetles have been 
detected. If these trees decline further, remove and destroy them. 
ive) 
Department of Biological Sciences, Northern Illinois University, DeKalb, Illinois 
=) 
ie) 
PUBLICATION RECEIVED 
Sex RATIOS AND AGE RATIOS IN NORTH AMERICAN DUCKS, by Frank C. Bell- 
rose, Thomas G. Scott, Arthur S. Hawkins, and Jessop B. Low. Available 
from the Section of Wildlife Research, State Natural History Survey, Ur- 
bana, Illinois. 84 pp., illustrated, paperback. $1.00. Checks should be made 
payable to the University of Illinois. 
Another excellent monograph on wildlife populations by our State Natu- 
ral History Survey, this time the product of 20 years of research. Conclu- 
sions reached are that: Unusually large numbers of drakes (sex ratio) or 
of old birds (age ratio) are signs that production of a species is dangerous- 
ly low. Of the two indicators, age ratios — especially number of young per 
adult — are the most reliable. The greater the number of juveniles in a 
population, the more nearly balanced is the sex ratio. These findings pro- 
vide a new and more valid basis for establishing future hunting regulations. 
As an outcome of the study, it was found that cold, excessively wet springs 
may be as deleterious to duck reproduction as dry, warm springs. ... Print- 
ing costs were financed by a loan from the National Science Foundation, 
and therefore it is necessary for the state to charge $1.00 per copy. 
Paul H. Lobik, 22W681 Tamarack Drive, Glen Ellyn, Ill. 
