Manipulation of Wood Growth by Chemicals

In the preceding section, further research was proposed on the use of chemical stimulants to induce cells to produce secondary metabolites in greater quantities 

A different type of example of cell change in response to an external stimulus is the formation of compartments (52) or barriers (5) in response to injury or infection. Zones of extractives-loaded parenchyma cells and swollen ray parenchyma cells are formed between infected xylem tissue and the healthy cambium. The zones act as a barrier allowing formation of new healthy xylem and protecting it from further damage by the pathogen of its metabolites. This reaction does not always take place. Elms Ulmus spp.) susceptible to Dutch elm disease do not 

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