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Dutch Elm Disease Had Abundance A landscape superintendent in ferred to as "the tree towns." ferred to as sanitation by forestry one of the Chicago suburban Elms, oaks and maples are indig- people. Since chemicals haven't towns recently stated that he enous in this sector and grow in yet been compounded that destroy thought Dutch elm disease had abundance. But the elms are either the beetle or its fungus, peaked in 1968 because "we have being cut down. The public works the only holding action possible reached the point where there are department in one of these towns, against the spread of Dutch elm hardly any more elm trees left to Elmhurst, reported that losses in appears to be sanitation. After the die." 1968 ran to 725 trees. That's ap- trees are removed they should be The statement wasn't quite ac- proximately 5 per cent of the elm burned. Otherwise, the beetles curate, but it did emphasize that population, and losses last year aren't going to be destroyed. the disease had taken an alarming were four or five times greater Golf courses that surround Chi- toll in 1968, far higher than in the than five years before. Glen Ellyn, cago are faring somewhat better last six or seven years. The Dutch at the western edge of the tree than municipalities in the battle elm blight was first detected in town sector, reported that nearly against the beetle. Their elm tree the Chicago area in 1955, but not 500 of its 10,000 elms were in- losses in 1968 probably didn't ex- until 1962 did it start making se- fected in 1968, the highest ceed 3 per cent, although a few rious inroads into the elm tree amount on record. Of an esti- superintendents reported that population. (The disease was first mated 60,000 elms in the Elm- from 5 to 10 per cent of their detected in the East in the early hurst-Glen Ellyn belt, about trees were denuded. Practically 1930s, and by the early 1940s was causing widespread destruction east of the Appalachians.) Each DUTCH ELM: year since then the casualty count has been of crisis proportions; last year the word "catastrophe" was WHAT IS IT? associated with it and by now, with the exception of the Far WHAT CAN West and Southwest, few areas of the country have been spared. BE DONE A sampling of the casualty fig- ures gives an idea of what has been happening around Chicago ABOUT IT? in the last few years: Lincoln By JOE DOAN Park, located on the lake front, in the last three years lost two-thirds 3,000 were lost. all of the superintendents agree of the 3,000 elms that once stood According to entomologists, a that last year was the worst for there, most of them victims of the beetle that is about one-tenth of the disease. blight. In 1968, 1,100 trees were an inch long and capable of flying Courses along the north shore lost. Most of them were at least relatively long distances is caus- of Lake Michigan seem to be 50 years old. ing the havoc. It either transports hardest hit of the Chicago clubs. Evanston, north of the city, a fungus or a fungus is spawned Probably this is because there are thought it was hard hit in 1965 from its eggs. The fungus then more elm trees concentrated in when 500 trees were marked for infests the tree's circulatory sys- this district than west or south of destruction. Last year the toll was tem and chokes off the flow of the city. Joe Dinelli, superinten- even higher; more than 650 trees moisture to its branches. Usually dent of North Shore CC, reported were condemned. within a few weeks the leaves that he lost 46 elms in 1968, al- To the south of the city, Home- wilt, turn yellow, curl and drop most exactly 5 per cent of the wood reported losses of only about off. When this happens there is number still left on his course. In 3 per cent in 1968, but since 1965 no chance that the tree can be five previous years a total of 110 more than 550 elms have died. An saved. It should be removed as elms at the club succumbed to the estimated 3,000 remain. soon as possible so that surround- beetle. Big holes are beginning to West of Chicago there is a belt ing trees aren't infected. appear in the wooded areas at of five contiguous towns that is re- Removal of dead trees is re- continued The fungus-carrying elm bark beetles tunnel (right) to the water-conducting ves- sels of a once-healthy elm tree (left). Result: fallen leaves in midsummer (center). Dutch elm disease continues to take its toll. In the hard-hit Chicago area, superintendents are carrying on a desperate fight using insecticides and replacement programs DUTCH ELM program. In the last two years the ion that as little time as possible continued club has spent $16,000 on tree should be lost in removing dead maintenance. trees. If they are allowed to stand North Shore and several trees, Like most superintendents, Di- until the end of the season, when strategic to play, have had to be nelli is wary of the anti-fungal it is more convenient to dispose of cut down. products that have been intro- them, surrounding trees may be- Two years ago, Dinelli stepped duced in recent years. There is come infected. Elm trees often die up replacement of trees that had little evidence that they have been in clusters, undoubtedly because had to be removed. Nearly a hun- very effective in arresting the of the delay in getting rid of those dred five- and six-inch maples, spread of Dutch elm disease. that die first. locusts, lindens and hackberries Their toxicity is feared in many Glen View CC and Evanston were planted in 1967 and 1968 to quarters. (See "DDT Panic," CC, both of which are fairly close replace the dead elms. Trees at June GOLFDOM, page 42.) The to North Shore, had about the North Shore are sprayed twice a North Shore superintendent has same loss experience in 1968 as year with DDT and one-quarter reached the conclusion that more the latter club. It was the highest of the 2,700 trees on and adjoining dependence should be placed on either of these clubs have re- the course are trimmed each year nature to check the blight. As far corded since the onset of the as part of a continuing pruning as sanitation, it is Dinelli's opin- blight six or seven years ago. Westmoreland CC, another in the immediate North Shore area, lost about 3 per cent of its elms in What's being done 1968, twice as many as it had ever which certain tree species either lost before. Julius Alspaugh, the The Elm Research Institute, attract or repel feeding by specific superintendent there, has been headquartered in Waldwick, N.J., insects. using a helicopter service to spray is a non-profit organization dedi- Michigan State University with his trees. He and about 10 other cated to the preservation of the $3,000 is breeding tiny wasps, im- superintendents in the Chicago American elm. It offers to its ported from Europe. The hatch district, who use an airborne members services which range larvae or pupae feed exclusively spraying service, say it is not only from counseling on elm care to on the larvae of the elm bark far more effective than ground field testing of new products for beetle. equipment, but about half as elm disease control. It will furnish Iowa State University with a expensive. stocks from its nursery for re- grant of $5,000 is studying the Fred Opperman of Elmhurst planting for the cost of packing responses in the tissue and chem- CC, a Westside club, lost about 4 and mailing. It also provides, istry of elms to infection by the per cent of his elms in 1968, as when requested, member groups pathogens of Dutch elm disease. many as he lost in five previous with a talk and color film on elm A film that will dramatize the seasons. Wes Updegraff of Oak conservation and maintains a li- urgency for support of the Insti- Park, which is near Elmhurst, brary from which members can tute's crash program is currently lost about 20 trees, rather alarm- draw material. under production. It will follow ing considering that an average of One of the major ways the In- the westward sweep of the dis- five had died each year in the last stitute combats Dutch elm disease ease, present current methods of five years. Updegraff doesn't is by giving research grants to en- coping with the disease and dra- spray, but gets rid of dead trees tomologists and plant pathologists. matize the effort now being made immediately, grinding up as many Currently, four universities are under the Institute's auspices. researching the problem through of their roots as possible. Both Special stamps are available in grants made by the Institute: clubs are in the middle of tree re- any quantity from the Institute. placement programs. Cornell University with a grant One stamp costs 10 cents; sheets of $75,000 is studying and inden- of 18 stamps are $1; pads of 12 Opperman favors different va- tifying characteristics of disease- sheets (196 stamps) cost $10. rieties of maple, hackberry, gink- resistant strains as a prelude to a Write: Executive Secretary, Elm go and oak.
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