The LI revealed it is facing even greater financial woes than previously thought, at an extraordinary general meeting last Thursday (22 January).
Chief executive Alastair McCapra said the major problem facing the LI was a rapid decline in advertising income. This came on top of problems from last year, which included a reduction in income from Gift Aid, loss of advertising revenue and accounting errors.
The economic downturn, along with increased fixed costs such as rent, had made matters worse, he added.
Members criticised the LI for not getting out news of the latest extent of cuts required more quickly. Planit IE director Peter Swift said he was shocked at the enormity of the institute's troubles: "I came to the meeting believing we were looking at £220,000 of cuts and that is not the case."
Robinson Landscape Design director Tom Robinson added: "It is unreasonable to be told we have a financial problem and not be presented with any detail of it.
"That is not how our organisation should be allowed to run."
Possible money-saving ideas include transferring the library and archive to another institution, dropping conferences in 2009 and reducing Landscape magazine from monthly to quarterly or twice-yearly.
Landscape architect Hal Moggridge said the library and archive was still a major issue among members and asked: "What will be the use of a body without an intellectual backbone?"
Past president Brian Clouston added: "There has been a huge loss of trust by the membership in the executive over the past few weeks."
But CABE Space enabler Annie Coombs said many members were prepared to help bail out the LI: "There have been some informal soundings around some practices and members, and we would be willing to give interest-free loans to the LI."
LI president Neil Williamson warned: "The financial position of the LI has changed even in the past few weeks."
McCapra added: "The rapidly changing business environment means is it difficult to be clear about future plans and the question is, how do we get through the next couple of years and emerge in some serviceable shape?
"We are in the middle of a really messy, untidy process. This means it is difficult to present members with a complete and final picture and there is not much point in taking a snapshot in the middle of it and expecting that to hold true as expected."
The LI council - which must make the final decisions on where the cuts will be made - will convene a further meeting before the end of February.
LI council member Ian Philips said: "We have clearly got to face some very difficult decisions, but we have to make the best business decision we can."
Policy officer posts in Scotland and Northern Ireland have already been made redundant.
LI Scotland chairman Hamish Neilson said: "There's a lot of resentment at the loss of the Scottish policy officer post. It is important there is seen to be parity of treatment ... across the UK."