The council is seeking community input on whether to protect a strand of 20-metre sugar gums lining Strada Avenue after an application by new tenant Monash Special Development School to remove them.

The school, backed by the Department of Education and Early Childhood Development, claims the 60-year-old trees are in dangerously poor condition.

The council countered that school builders had damaged the trees' root systems during the recent construction of a fire service water main.

Monash Mayor Paul Klisaris said the works were "contrary to an agreement with the council", and subsequently five "historically significant" sugar gums in poor health would be urgently removed.

Another sugar gum would be removed for driveway access, while 11 'unsafe' trees on the rest of the site had been earmarked for removal.

The council may protect the remaining sugar gums with a heritage overlay, subject to feedback from a community forum.

Cr Klisaris said the department agreed "in principle" to retain trees on the rest of the site during demolition works - set to begin before July - until the trees' potential was assessed.

A department of Education and Early Childhood Development spokeswoman said the builder of the fire main had undertaken works "some distance" from the trees.

"A Department-commissioned arborist indicated the trees were unsafe before the works, and the builder and project architect don't believe any further damage was caused by their actions."

She said the six trees would be removed as soon as possible and replaced after construction.

Brandon Park Resident Action Group spokesman John Shrives said the group wanted as many trees as possible to be retained.

"The trees are quite significant because of their size. Not many trees there are like that now. That's the last large strand of trees until you get to Jells Park."

Monash University urban planning expert Bob Birrell said trees were becoming more scarce in Monash because of denser housing development.

"People regard that leafy canopy of suburbia as part of their quality of life and residents are unhappy that it's disappearing."

The National Trust of Australia (Victoria) has more than 1000 trees listed on its significant tree register, one of which is in Monash - a flowering gum outside the Metropolitan Golf Club's clubhouse in Oakleigh South.

National Trust cultural heritage manager Tracey Avery said further nominations for significant trees were welcomed.