PINE BLISTER DISEASE WORK PROGRESSES 



THE organization of the campaign against the white 

 pine bhster disease has gone forward steadily. 

 Many of the state appropriations were delayed 

 six weeks or two months beyond their ordinary course on 

 account of the pressure of National Defence measures. 

 Fortunately the season was much later than normally 

 is the case. A few fruiting pine specimens were found 

 early in May, but it was the middle of May before the 

 pines in the heavily infected localities of New England 

 showed an abundance of blisters. The first stage of the 

 disease on currants and gooseberries was discovered on 

 June 5, the same date on which it appeared last season. 

 The second stage of the currant rust was found on June 

 13, ten days earlier than last year. 



The results of scouting to date have shown conditions 

 to be just what was feared last year as a result of the 

 wide distribution of the blister disease on currants and 

 gooseberries throughout New England. At all of the 

 points where diseased native pines existed last year the 

 disease was found to make steady progress. For instance, 

 one tree in the Kittery Point infection area, 38 feet 

 high, was being girdled on the main stem at a point 20 

 feet above ground where the circumference of the trunk 

 was 23 inches. All of the side branches on this tree — 

 more than 100 — were infected with the blister rust, as 

 the bright colored blisters plainly proved. In addition to 

 the increased size of the infection areas at Kittery Point, 

 Swansea, Massachusetts; Stratham, New Hampshire; 

 Lyndonville and Woodstock, Vermont; Essex County, 

 New York, and Norfolk, Connecticut, many new areas 

 of infected pines, both planted and native, were found 

 in these states. One of the most serious is at Intervale, 

 New Hampshire, near the Cathedral Pines. On a pine 

 hedge near the Cathedral Pines, 1021 infected branches 

 were removed and about 90 infections taken from a single 

 tree. On another property where there were a dozen 

 heavily infected black currant bushes in a garden there 

 were a number of infected pine trees about 40 feet distant. 

 One of these trees, 6 feet high, had 26 separate blister 

 rust infections and showed indications that many more 

 infected branches were developing. Infected pines were 

 found on other nearby properties and the pines of the 

 whole region are apparently in the greatest immediate 

 danger if not already hopelessly diseased. 



Currants and gooseberries, both wild and cultivated, 

 at this early date, are already heavily infected in regions 

 where pine infection is plentiful. Currants and goose- 

 berries in Maine are about as heavily infected now as 

 they were last year in August and September. Between 

 Brunswick and Bath, Maine, they are generally in- 

 fected ; that is, careful observation shows that it is safe 

 to estimate that 90 per cent of all these plants are in- 

 fected now. Many plants already have infection on prac- 

 tically every leaf. This condition existing so early in 

 the season (the latter part of June) indicates that these 

 plants .must have been directly exposed to spores from 

 pines. Infection is especially heavy on skunk currants. 



Pine infection is well scattered between Brunswick and 

 Bath. At Bath there exists a comparatively large area 

 which contains at least 90 per cent of infected white pine 

 trees. Many of these have fruited during the past season. 

 On one young tree 35 infected branches were noted. The 

 oldest infection found in the Bath area appears to have 

 taken place about eight years ago, probably less. 



The wild currant and gooseberry bushes along one 

 side of the highway between the villages of Warren and 

 Wentworth, Grafton County, New Hampshire, were 

 examined; 91 per cent of the plants proved to, be infected. 

 In New York State pine infections were found scattered 

 over a number of square miles of fine native pine growth 

 in Essex County and infected currants have been found 

 in Clinton and Niagara Counties. Only one new infec- 

 tion has been found in Pennsylvania, and Michigan has 

 also been added to the list of infected states through dis- 

 eased pine stock found in a nursery. In Minnesota five 

 new points of infection have been found at Afton, Marine 

 Mills, Pine Hollow (opposite Osceola, Wisconsin), at 

 Franconia, and on the water supply reservation at 

 Lake Vadnis. 



Until recently considerable effort was expended in 

 scouting localities where infection was known to exist 

 last year and diseased pines were destroyed. The efforts 

 during the balance of the summer will be confined princi- 

 pally to controlling the disease by destroying currants and 

 gooseberries. The work of eradication is being pushed as 

 rapidly as possible. In each of the New England States 

 one or more areas of heavy pine growth have been 

 selected for the destruction of all currants and goose- 

 berries. These areas will serve to demonstrate the feasi- 

 bility of controlling the disease and the boundaries of 

 the areas will be extended as rapidly as possible. In New 

 York the heavily infected pine area in Essex County is 

 being isolated by pulling currants and gooseberries from 

 a strip two miles wide which, when finished, will extend 

 through the Ausable Valley, from the Canadian border to 

 Lake George. Last year a strip of this character was 

 made through Columbia County, New York, to stay the 

 advance of the disease from Massachusetts. Later in tlie 

 season this line probably will be extended northward 

 through Rensselaer and Washington Counties to Lake 

 George. A similar strip a mile wide is being cleared of 

 currants and gooseberries from Lake Ontario to Niagara 

 Falls and the southern extremity of Grant Island. This 

 strip was cleared on the suggestion of the Canadian 

 authorities, who are now completing the eradication of 

 currants and gooseberries from a mile-wide strip along 

 the Niagara River from Niagara-on-the-Lake to Fort 

 Erie. A large force of scouts is engaged searching for 

 the disease in all of the eastern states where the disease 

 was not found last year, including the Southern, Rocky 

 Mountain and Pacific Coast States where five-leaved 

 pines are native, but special attention is being given 

 outside of New England and New York to the Lake 

 States. 



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