Soil Temperature Chart
The use of soil temperature data is certainly useful for predicting the germination of annual weeds like Poa annua (21ₒC), Eleusine indica (16-18ₒC) and Digitaria sp. (12-15ₒC).
Download Soil Temperature Chart
This will then help with correct timing of pre-emergent herbicide treatments. But soil temperature can also be a useful tool for predicting disease activity, turfgrass growth patterns and to a lesser extent, insect activity. The chart shows critical soil temperature ranges which may be useful for turf managers. Most of this information is from the US and should be appropriately used and adapted to Australian conditions. Soil temperature information data can be obtained from the Bureau of Meterorology website (www.bom.gov.au) but measurement of temperature on site will be most valuable as significant variation can occur even across small distances depending on soil type, turf cover, aspect, shade, etc. It is important to note that turf cover will have an insulating effect on soil temperature and so on site results may vary from those measured by the Bureau.
NB: Critical Soil Temperatures in Turfgrass Management* (measured at 10cm depth) *information primarily sourced from North Carolina State University