The IPSN (International Plant Sentinel Network) has developed a number of resources to aid plant health/biosecurity activities in botanic gardens and arboreta. This includes providing guidance on types of pests and diseases, good biosecurity practise, information (and identification guides) for current threats plus much more.
The network has created a standard surveying form to support monitoring/surveying actitivies. The IPSN Plant Health Checker has been specifically designed to help assess damage in trees with unknown pest/disease problems. It helps garden staff to survey, record damage and generally assess health problems in tree species.