|MadSci Network: Botany|
Aspirin contains salicylic acid which is known to prevent the growth of microorganisms found in water. Salicylic acid is produced by some plants in response to attacks by pathogens and so it may have some protective function. This chemical also acidifies water and acid solutions move up the stem more readily. However in the typical cut flower and in your case Christmas tree, aspirin does not seem to have a huge effect. Work done on Fraser Fir indicates that using aspirin may in fact cause much more needle drop than plain water. A number of different chemicals and chemical mixes were tested. It turned out that there were two outcomes. One, as was the case with aspirin, resulted in increased needle loss. The other result was that no treatment was better than water. The take home message is that the only thing necessary to keep the needles on the tree is water. So while adding aspirin to water used in cut flowers may only slightly enhance longevity (in reality there doesn't seem to be much significant difference between using aspirin or water alone) at least in Fraser fir there seems to be very significant needle drop. Don't use aspirin on your cut Christmas tree! http://www.pathfastpublishing.com/..\qr28\ethydise.htm http://henderso.ces.state.nc.us/newsarticles/ag/98-12-14ml.shtml
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