Minimal Disease Treatment Level: There are no restrictions on stand management operations. However, where armillaria root disease is not completely absent from the stand or stratum, one should attempt to favour tolerant or moderately susceptible species as crop trees where ecologically appropriate. This practice will increase the number of barriers acting to deter the spread of the fungus between susceptible host species. The high susceptibility host species should be restricted to less than 20% of the stand composition. Alternate Disease Treatment Level: There is a risk when spacing of increasing mortality from armillaria root disease by increasing the inoculum levels. Highly susceptible host species should be restricted to less than 20% of the stand composition. Consult your regional forest health specialist for clarification. The main strategy to manage armillaria in young stands is to favour moderately susceptible species, especially where they can act as a buffer surrounding an infection centre or tree. It is important to retain these less susceptible tree species when they fall within 5 m of an infected tree or centre. Broadleaf tree species may be the only choice in areas with high levels of root disease and limited alternative coniferous species. Intensive Disease Treatment Level: This level of incidence signals caution if considering treating these stands. Stands may require restratification (see Figure 1 for examples), alternative spacing techniques, delay in spacing activities, or no spacing at all. Consult with your regional forest health specialist before proceeding. Block A – restratification possible Block B – restratification possible Block C – restratification not possible
Minimal Disease Treatment Level: There are no restrictions on stand management operations. However, where armillaria root disease is not completely absent from the stand or stratum, one should attempt to favour tolerant or moderately susceptible species as crop trees where ecologically appropriate. This practice will increase the number of barriers acting to deter the spread of the fungus between susceptible host species. The high susceptibility host species should be restricted to less than 20% of the stand composition. Alternate Disease Treatment Level: There is a risk when spacing of increasing mortality from armillaria root disease by increasing the inoculum levels. Highly susceptible host species should be restricted to less than 20% of the stand composition. Consult your regional forest health specialist for clarification. The main strategy to manage armillaria in young stands is to favour moderately susceptible species, especially where they can act as a buffer surrounding an infection centre or tree. It is important to retain these less susceptible tree species when they fall within 5 m of an infected tree or centre. Broadleaf tree species may be the only choice in areas with high levels of root disease and limited alternative coniferous species. Intensive Disease Treatment Level: This level of incidence signals caution if considering treating these stands. Stands may require restratification (see Figure 1 for examples), alternative spacing techniques, delay in spacing activities, or no spacing at all. Consult with your regional forest health specialist before proceeding. Block A – restratification possible Block B – restratification possible Block C – restratification not possible
FS448a.docx