We always try to count and weigh at least a subset of our accession. In large accessions with many seeds, we generally count, weigh, and split the first 30 maternal lines. After 30 we record the weight of the maternal line and split it by eye. If your maternal lines have thousands of seeds you might count and weigh groups of 100 to 500 seeds. Once we establish the seed count/mass ratio we have an Excel sheet that will plot and graph our data. We can then estimate the seed count by weight.
Hope this makes sense. Feel free to email if you have questions or want the Excel/data sheet!
Joe Davitt – jdavitt@sandiegozoo.org
San Diego Zoo Global Native Plant Seed Bank