From these twigs, needles of various ages were examined in a laboratory at the University of Guelph for the presence of symptoms of disease and for signs of pathogens. Spore production of needlecast fungi was assessed at both sites, through weekly collections of twigs from at least three trees per location. In 2008, three spray applications of fungicide were made to each test branch, with a target interval of 10 days, starting at shoot emergence. A number of fungicide active ingredients including azoxystrobin, myclobutanil, propiconazole, pyraclostrobin and boscalid, trifloxystrobin, sulphur and mancozeb + myclobutanil (Nova Scotia only) compared to the industry standard, chlorothalonil, were evaluated at both sites. kalkhoffi and Stigmina lautii on blue spruce at the Nova Scotia site, the main target pest was L. At the Ontario site, the main target pests were R. In this multi-faceted trial, seven new active ingredients, selected based on their efficacy against related fungi and availability, were screened for efficacy against needlecast diseases.Įxperiments were conducted in 20 at two sites in Ontario and Nova Scotia. Screening trials and subsequent efficacy trials that lead to new fungicide registrations for conifer needlecasts, would arm growers and landscapers with efficacious rotational products. The few fungicides available to control needlecast diseases often did not provide adequate control. At the initiation of this project, recommendations for the control of needlecast diseases were to apply fungicides to the current season's growth from bud break to hardening off (late summer). The presence of Rhizosphaera needlecast on spruce is a concern in Ontario because of the unsightly appearance of infected foliage and threat it poses to tree health. The presence of Lirula needlecast can result in conifer tree growers having to trim off the lower diseased branches in order to have saleable Christmas trees, thus significantly lowering the wholesale value of the trees. Two common needlecast diseases include Lirula needlecast caused by Lirula nervata on balsam fir and Rhizosphaera needlecast caused by Rhizosphaera kalkhoffi on spruce. In Canada, needlecast diseases present some of the greatest challenges for commercial conifer tree growers and are also a significant issue on conifers that are established in the landscape and in windbreaks. In addition, methods to detect the presence of the pathogens in asymptomatic needles will be developed. To assess the potential of selected fungicides for needlecast control on two conifer species, Colorado spruce ( Picea pungens) and balsam fir ( Abies balsamea) and to provide recommendations for candidate fungicides to be pursued for registration in Canada. If any of these conditions happen, the tree may turn an ungainly shade of brown and look almost dead.Jim Jotcham - Marbicon Incorporated Objective Also, you mustn’t overwater these naturally hardy trees which can make do with a little amount of water. Though there are no specific sizes on how deep you must transplant your spruce tree, make sure that you don’t transplant it too deep. Tip 3 – Don’t Overwater or Transplant too Deep That is the reason you need to plant these trees as far as possible to save from possible interference from the tree to your house and weakening of its foundation by the roots. The trees themselves can grow as high as 60 feet and can occupy a horizontal space of 15 to 20 feet. The roots of the spruce can go deep into the ground in search of water and they can become quite strong. This is an important and often-neglected point. Tip 2 – Transplant Your Spruces Away from the House You have to make sure you select a spot that receives at least 6 hours of direct sunlight every day and plant your spruce there. In the absence of direct sunlight, their growth can even be stunted. These are trees that compete for sunlight in the wild and hence grow as tall as they possibly can. Tip 1 – Choose a Place with a Good Amount of Sunshine Here are some tips that will help you transplant a better spruce tree. You will need to take extra care after transplanting or planting up to 4 years to give the tree the best chance possible of reaching maturity. Never put the manure too close to the base of the tree. Keep the area mulched and give the tree nutrients by placing fertilizer or manure near the roots. Remember to keep the tree well watered, but with enough drainage so it is never standing in water. Spraying the tree with chlorothalonil is usually effective in treating this sort of problem. Rhizosphaera is a fungus infection that also turns the needles yellow. Spruces are susceptible to such disease as the lirula needle blight, which turns the needles yellow or brown.
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