Tree diseases

Tree Disease Concepts. 2nd Ed. Manion, P.D. Prentice-Hall Englewood Cliffs, NJ, 1991. 

Allen, E., D. Morrison, and G. Wallis (1995). Common Tree Diseases of British Columbia, Natural Resources, Canada. Victoria, BC Canadian Forest Service, 178 pp. 

What do we mean when we say a plant is diseased If you accidentally skin the bark off the base of a tree with your lawn mower, is that tree diseased If spring frosts. slightly burn the leaves on broccoli transplants, are those plants diseased Are pea plants infected with beneficial root-nodule bacteria diseased ... 

Rot fungi, soil-borne fungal pathogens tree diseases Spider mites... 

The devastating tree disease, which has wiped out elm trees in almost half of the United States, could not be controlled successfully with either insecticides or fungicides. It seems, however, that the problem can resolved by the application of a synthetic mixture of the three compounds. 

Bark beetles. Insects related to the weevils that bore into the wood and bark of trees and often cause extreme economic damage to forests. Many species live in symbiosis with fungi the elm bark beetle Scolytus multistriatus transmits the feared elm tree disease caused by the fungus Ceratocystis ulmi. Some B. species are controlled by the application of synthetic pheromones in trap devices, that contain combinations of pheromones with synthetic insecticides see also bre-vicomin, chalcogran, conophthorin, frontalin, ipsdienol, lineatin, multistriatin, pityol, sulcatol, seudenol. 

Manion P D 1981 Tree disease concepts. Prentice-Hall Englewood Cliffs, 399 pp... 

The fungus responsible for Dutch elm disease is spread by European bark beetles when they burrow into the tree Other beetles congregate at the site attracted by the scent of a mixture of chemicals some emitted by other beetles and some coming from the tree One of the compounds given off by female bark beetles is 4 methyl 3 heptanol Suggest an efficient synthesis of this pheromone from alcohols of five carbon atoms or fewer... 

Cyasin, a component of the nut of the cycad tree, a native of tropical environs, produces an acute toxicity in addition to drastically increasing the incidence of Lou Gerhig s disease (amyotropic lateral sclerosis). Cyasin is carcinogenic (102). 

The function of the essential oil in the plant is not fully understood. Microscopic examination of plant parts that contain the oil sacs readily shows their presence. The odors of flowers are said to act as attractants for insects involved in pollination and thus may aid in preservation and natural selection. Essential oils are almost always bacteriostats and often bacteriocides. Many components of essential oils are chemically active and thus could participate readily in metaboHc reactions. They are sources of plant metaboHc energy, although some chemists have referred to them as waste products of plant metaboHsm. Exudates, which contain essential oils, eg, balsams and resins, act as protective seals against disease or parasites, prevent loss of sap, and are formed readily when the tree tmnks are damaged. 

The first clues to the treatment of scurvy occurred in 1535—1536 when Jacques Cartier, on advice from Newfoundland Indians, fed his crew an extract from spmce tree needles to cure an epidemic. Various physicians were recommending the use of citms fmits to cure scurvy in the mid-sixteenth century. Two hundred years later, in 1753, it was proved by Dr. James Lind, in his famous clinical experiment, that scurvy was associated with diet and caused by lack of fresh vegetables. He also demonstrated that oranges and lemons were the most effective cure against this disease. In 1753, inM Treatise on the Scurvy[ Lind pubhshed his results and recommendations (7). Eorty-two years later, in 1795, the British Navy included lemon juice in seamen s diets, resulting in the familiar nickname "limeys" for British seamen. Evidence has shown that even with undefined scorbutic symptoms, vitamin C levels can be low, and can cause marked diminution in resistance to infections and slow healing of wounds. 

Chinese Liver Fluke. The adult worm of the Chinese Hver fluke Clonorchis sinensis) can grow to be 2 cm long. Worms infect the bihary tree where they cause local inflammation, diarrhea, and hepatomegaly in the acute infection. Progressive biUary obstmction and cirrhosis can occur in the more advanced disease state. The presence of 20—200 worms is common, but they may number over 20,000. Infection is the consequence of eating raw fish that contain viable parasites. Untreated worms can Hve for up to 30 years. Treatment is with pra2iquantil (1). 

Chymopapain [9001 -90-6] derived from the latex of the papaya tree, produces improvement in lower back pain and sciatica in the majority (75%) of recipients (185—189) when injected into the lumbar intervertebral disks of patients suffering from herniated disk (the nucleus pulposus). This treatment degrades the proteoglycans of the diseased nucleus pulposus, resulting in shrinkage of the disk and reduction of pressure on the nerve roots (190). 

Pinworm is a helminHi infection that is universally common most oHier helminth infections are predomi-lianHy found in countries or areas of the world that lack proper sanitary facilities. Malaria is rare in the United States, but it is sometimes seen in individuals who have traveled to or lived in areas where this disease is a healtii problem. The first antimalarial drug, quinine, is derived from the bark of the cinchona tree. Amebiasis is seen Hiroughout the world, but it is less common in developed countries where sanitary facilities prevent Hie spread of the causative organism. 

Sympathomimetics (drugs that mimic the sympathetic nervous system) are used primarily to treat reversible airway obstruction caused by bronchospasm associated with acute and chronic bronchial asthma, exercise-induced bronchospasm, bronchitis, emphysema, bronchiectasis (abnormal condition of the bronchial tree), or other obstructive pulmonary diseases. 

Gnkgo (maiden hair tree, kew tree) Ginkgo biloba Raynauds disease, cerebral insufficiency anxiety, stress, tinnitus, dementias, circulatory problems, asthma Rare if used as directed possible effects include headache, dizziness, heart palpitations, Gl effects, rash, allergic dermatitis Do not take with antidepressant drugs, such as the MAOIs, or the antiplatelet drugs such as coumarin, unless advised to do so by the primary care provider. 

Obviously, one looks for causes. That declines in one or another species have natural factor etiologies is unequivocal. The demise of American elms and of the chestnut were due to natural factors. Insect infestations, bacterial and fungal diseases, hurricanes, floods, freezes, droughts and many other stresses can cause extensive tree death (5). But in such declines typically only a single species is affected or climatic events caused decline in a delimited area. In almost all declines caused by natural events, the causal factors can be identified we know their precise etiologies. Natural events are always part of the natural environment and must be factored in when evaluating forest declines (Table I). 

One of the first and most useful medicinal chemicals is aspirin (CgHgO ), also known as acetylsalicylic acid. This painkiller was first trademarked and manufactured in 1899, but a precursor to the drug had been extracted from the bark of willow trees by Hippocrates as early as the 5th century b.c. The pharmaceutical industry has since developed an array of products to alleviate aches and pains, yet aspirin is still prominent on the shelves of drugstores. In pharmacies that dispense prescription drugs, an even wider array of chemicals is sold to help those with diseases ranging from high blood pressure to cancer. 

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