CLONES AND GROWTH

PLANT ECOLOGY LABORATORY

Location: Prairie Island

Objective: To examine the ages and growth of clones of an invasive, woody plant in mixed prairie/woodland habitat

Hypothesis: Clones will display symmetric growth in all directions from the parent plant(s).

Agenda:

1) Work in groups of 6-7 students to assess the age and growth patterns of clumps of staghorn sumac (Rhus typhina) clones.  Locate and mark the largest/oldest stems, and define the outer boundary of the clump before beginning measurements.

2) For each stem within the clump, measure the distance from and direction relative to the oldest stem.  Measure the height and basal diameter of each stem, and determine its age.  Continue until all stems have been located and measured.

Analysis:

1) Using an appropriate scale, create a map of the locations of each stem within the sumac clump, using different symbols or colors to denote stems of different ages.  Is the growth pattern of the clump symmetrical around the oldest stem(s)?

2) Use regression analyses to examine the relationships between 1) stem age and height,  and 2) stem age and basal diameter.  Is stem height or basal diameter the better estimator of stem age?

3) Use regression analysis to examine the relationship between stem age and distance from the oldest stem.

Equipment:

Meters tapes, calipers, compasses, flagging, data sheets