Forest Research serves Scotland, Wales and England representing the only grouping of forest scientists in the UK capable of delivering scientific advice and research on British forestry across a broad range of topics and disciplines.
But Prospect warned that this expertise could be fragmented by funding cuts and plans by the devolved administrations to break away and form their own bodies.
Prospect negotiator Malcolm Currie said: "We are disappointed and very surprised that Forest Research is only mentioned twice in this 70-page report because it was flagged up to the panel in our evidence.
"Forest Research has already suffered a 28 per cent cut in staffing which risks fundamentally compromising its ability to perform its functions. Universities and research councils are not interested in doing this work. So who will? Indeed, who else can?"
Government spending on research in the forestry sector up to 2015 will be cut by 40 per cent. Forest Research concluded that the cuts were too deep to allow it to continue research in all its current fields.
"Our fear is that Forest Research could shrink to a size where its viability is difficult to sustain," said Currie.
For example, management of current and emerging pests, weeds and disease through the sustainable use of pesticides and other non-chemical methods has been cut by 60 per cent. Habitat management to improve biodiversity has been cut by 75 per cent.
Forest Research's ability to deliver advice and research on British forestry lies in its network of sites and field stations – which between them provide geographic coverage of woodland throughout England, Scotland and Wales.
"The field stations, and the highly skilled research workers based at them, are a unique resource. The geographical coverage, local knowledge, relationships with landowners and the technical skills at these field stations enable FR to enjoy unparalleled access to sites to undertake field trials and experiments.
"FR also undertakes a wide range of survey work to gather datasets representing the full range of climatic and ground conditions across Britain," he added.
Currie agreed with the panel that capacity needs to be retained at GB level. "We welcome the panel's recommendations on investment and development of services and its recognition of the professionalism and dedication of FC staff.
"But it's a shame that they couldn't join the dots and make the case for giving Forest Research the funding and staff it needs to do its job across the whole of the UK," he concluded.