FIREBLIGHT

Nelson Evening Mail, Volume LXIII, 16 July 1929, Page 6

FIREBLIGHT

—♦ — CONTROL OF THE DISEASE INSTRUCTIVE ADDRESS At the monthly meeting of t~io Mahana Fruitgrowers' Association, Ltd., there was a fair attendance of members, the president (Mr Noble-Camp-bell) presiding. It was decided to pay a visit to scone of the Stoke orchards at an early dute, tire secretary to get in touch with the kelson orchard instructor, .Mr Thorp, and arrange an itinerary. The matter of tho nomination of candidates for the Fireblight Committee came before the meeting, and in view of the decision of the. meeting of representatives of associations held recently ill Nelson to distribute the members of the committee evenly throughout the province, it was unanimously decided to nominate Mr J. Dicker, who is already the Hills Union nominee. The next meeting will be held on the 24th inst., when Mr E. C. Bensemann will give an address on orchard manuring. There will be other important business for discussion and to allow as much time as possible for the important subject of the address, it was decided to meet at 7 p.m. It was also decided to apply to the Chief Postmaster at Nelson for a slight change in the carriage of the outgoing mail from Mahana on three days a week, which would be of advantage to the settlers. FIREBLIGHT CONTROL Mr Huia Bensemann gave a most interesting address on the subject of "Fireblight'Control." He went to considerable trouble in preparing his subject by illustrating the various stages of the disease and showing the methods used in California by surgery work for its 'control. He first of all explained the virulence of the disease and- its'meaus of spreading from one part to another, insects being the chief of these, while implements or pruning shears and saws particularly were responsible in a large, measure foN carrying infection when the disease had once got into an orchard. A fireblight canker was the first illustration, showing .the infected bark broken away and receded from,the healthy bark surrounding. From the bottom of this an oofce appeared resembling at first dew drops, but later turning a yellow colour. This ooze is sweet and consequently insects suck it and then carry to blossoms and leaves infection which "very quickly runs down into the wood 'and the whole of the infected part turns black.

In a tree growing strongly with a good flow of sap, , the blight moves rapidly up and down, whereas in a weaker tree the spread is not so rapid. Mr Bensemann explained that no tree, strong or weak, was immune from infection, and the same care in control had to be exercised in all cases. The speaker then went on to explain the method of "cutting out" employed in America. Special men are engaged examining the trees and looking for infected, parts .and attending to the cutting but of these when found. Where infection is 'found in th e tips of laterals,' these are cut off tight up against the limbs, and. if a saw is used for this cut, a cut should be made underneath first so that the bark of the main limb is not torn when the branch falls. The wound heals up much quicker, too, if cut in this and there is less chance of fhrther infection. Any other laterals which niight have been touched by the infected part through wind action, must also be cut away. Any parts cut off are never touched by hand and are gathered up with forks and carted away and burnt the same day.' Mr "Bensemann gave the formulae of the disinfectants used in New Zealand and the /United States, and stated that all tools are disinfected before and after every cut and hot tar is painted over the' wounds, to stop any fresh entry of the disease. He then explained the method of treatment when infection entered a limb. The outer bark is scraped nine inchs above, and below the infection, and if the disease is present, it shows blood red in the cambium. The whole of this infected cambium must be cut right out and the limb painted with a disinfectant. When the blight once gets below the crutch it is past any treatment and must be dug out and burnt. Mr Bensemann explained that a resistant stock had been found for pears and was now being used in America. This is budded when five or six years old with the Bartlett pear, and if fireblight attacks this they do not have the risk of losing the whole tree. On il.e. river farms in California, where Mr Bensemann spent some time, thirty men were employed for the control of fireblight alone, and it took them ten days to go over the whole orchard. This cost the river farms equal to 12s per tree for the control of fireblight, proving a very costly business. . in conclusion, Mr Bensemann stressed the necessity of doing everything possible to keep fireblight out of Nelson. He thought every grower should nave a knowledge of the appearance of fireblight and also of the methods employed in dealing with it should an outbreak occur, and eveiy grower should be on the watch all the time. A hearty vote of thanks was accorded Mr Bensemann for his interesting and instructive address, and the opinion was expressed that such an important subject was worthy of a much larger audience. It was decided to ask the Hills Union to call a meeting at an early date, and in a central place to hear Mr Bensemann's address. In returning thanks Mr Bensemann stated that he would be glad to address other meetings if desired. Gratification was expressed in that a number of farmers in the Waimeas had cut and trimmed their hawthorn hedges. This has not gone unnoticed by the fruitgrowers, and they wish to express their gratitude to the farmers concerned. It was decided to ask the Horticultural Department to again supply two men to patrol the hawthorn hedges of the district during the spring to report any signs of the disease.