Some leaves can live for decades, but most have a limited lifespan.

Agriculture is mostly about keeping foliage alive, so it seems pretty important to try to understand the built-in obsolescence of leaves.  That's what I've been doing for most of the last thirty-odd years.  The following link leads to a personal view of how and why leaves end their lives:

For a global view of research on plant senescence, the people who carry it out and the activities, achievements and resources of the plant senescence community, click this link to plantsenescence.net:

The literature on plant senescence is extensive. As well as my own publications (listed here), you can find a selective and growing senescence bibliography by following this link:

With financial support from the Leverhulme Trust and the technical assistance of Suzy Shipman, I'm slowly building the framework of a senescence wiki.  We hope this will grow into a broader, deeper and more rigorously scholarly treatment of the subject.  Most importantly, it will be open for contributions from other experts so that it becomes better balanced, less prejudiced and more representative of the views of the senescence community as a whole.

Here is a copy of a poster advertising SenWiki.  You can check on progress, and by all means contact us about submitting an article, by clicking on the button: