Comparing growth of ponderosa pine in two growing media
This article is part of a larger document. View the larger document here.Abstract
I compared growth of container ponderosa pine (Pinus ponderosa) seedlings grown in a 1:1 (v:v) Sphagnum peat moss:coarse vermiculite medium (P:V) and a 7:3 (v:v) Sphagnum peat moss:Douglas-fir sawdust medium (P:S) at three different irrigation regimes. By using exponential fertilization techniques, I was able to supply seedlings with similar amounts of fertilizer over time even though irrigation frequency differed. Although I noted a reduced growth rate in P:S seedlings, final morphology was, for the most part, similar to their P:V cohorts. When given similar rates of fertilizer, seedlings grown at reduced irrigation frequencies were fairly similar to those given robust amounts of irrigation, indicating that growers may be able to reduce irrigation frequency without a loss of stock quality.

