The proportion of heartwood to sapwood in the main stem does vary with species. Black locust, for example, usually has a very narrow band â often less than an inch â of functioning sapwood, whereas maple stems often can have many inches of sapwood and relatively narrow cores of heartwood.he proportion of heartwood to sapwood in the main stem does vary with species. Black locust, for example, usually has a very narrow band â often less than an inch â of functioning sapwood, whereas maple stems often can have many inches of sapwood and relatively narrow cores of heartwood.
1 Apply stain only at the proper temperature. 2  For most stains, 70 degrees Fahrenheit is the optimum, with the safety range from 50 to 90 degrees Fahrenheit. 3  Stains do vary, so check the label first.o assure the highest quality results when applying exterior wood stain, follow these steps and helpful tips from Sherwin-Williams stain experts. 1  Use the right brush. 2  Use a natural-bristle brush for oil stains and a synthetic-bristle brush for latex stains.
Application temperature must be a minimum of 60Â°F and rising. Do not apply when temperature is expected to drop below 60Â°F within a 24 hour period. In areas where dew or fog accumulates in the early evening, it is best to coat in the morning.or optimum performance (and warranty purposes) apply two coats at an application rate of no more than 350 square feet per 5-gallon pail per coat. Allow first coat to dry completely before applying second coat. Allow sealer to cure 24-48 hours before opening to vehicle traffic.