Aspen fertility declines in old age

Aspen clones are known to live to a ripe old age, but just how long has largely been a matter of speculation rather than science. However recent research in British Columbia has shed some light on the ageing process in aspen.

Ally, Ritland and Otto studied clones varying in age from 70 to 10000 years. They found that clones senesced with increasing age, as demonstrated by a slow but steady decline in fertility.

http://www.plosbiology.org/article/info%3Adoi%2F10.1371%2Fjournal.pbio.1000454

So, over the long-term, aspen's survival relies on periodic renewal through sexual reproduction.

We don't know how old Scottish clones are, but this work supports efforts to propagate aspen from seed.