notes Growing from soil hidden fairly-deep beneath the unstable scree on the steep slope of an old quarry...an unusual substrate for Collinsia. A remarkable aspect of this population is that the roots, hidden from view by the scree, have an unusually long distance to traverse between the actual soil below the scree and the sun-lit space above the scree.
In particular, germinating seeds here have a longer than usual 'growth distance' to:
1) send roots down into productive soil below;
and/or
2) send their initial leaf shoot up into available light above the deep scree.
The relatively exposed & soil-free rock interstices of the scree would seem a relatively stressful micro-environment for that intermediate portion of the roots.
