Middle Bear
From UA Sky School Wiki
Middle Bear
Note: we rarely visit this stop now
Dendrochronology
- Great root sticking out over eroded hillside that tree ring has cookie slice from the end that matches perfectly
- Root was cut to determine how long ago the hillside eroded: Did the picnic area developed in the 1960's cause the erosion?
- A fire scar on the root from over 100 years ago showed it was already exposed back then. It eroded before the picnic area was built.
- Why do trees make rings? What kind of environments will produce tree rings?
- What is the tradeoff between safety and efficiency in xylem? (Larger conduits = more flow, less drought resistance, less dense wood (early season); the opposite late season as drought occurs)
Fire ecology
- Don't fires destroy trees and forests? How do we see fire scars?
- (Answer: fires can burn the brush at the base without lighting a large tree all the way on fire. The damaged bark will try to grow back around it, creating what is called a "catface" (don't know why). These are usually found on the uphill side of trees because pine needles and other dry material collects there and catches fire.)
- What is the difference between a ground and a crown fire? What dies in each case?
- How are different species adapted to fire? (protection vs regeneration)
Soils/Erosion
- Note the long gullies and large coarse sand in the washes. How would this soil erode compared to other sites?
- Does fire destroy organic (carbon-rich) layers of the soil? Do these layers stabilize the soil? What about roots?