Winter Buds

How to collect winter buds of lowbush cranberry

Season for activity: Late fall when temperatures are consistently freezing and throughout the winter

Time commitment: 1.5 hours - One time only

Materials needed:

  • scissors to cut 10 lowbush cranberry stems with flower buds on them
  • ziplock bag
  • shovel (if there is snow)
  • datasheet (download and print here)
  • manila envelope and postage for sending samples

Overwintering buds on lowbush cranberry (Vaccinium vitis-idaea) look like this. This is what you will collect. Photo by C. Mulder

Sampling Directions:

1. Once the temperature is consistently below freezing, go to a site that you have seen flowering or fruiting lowbush cranberry plants. It doesn’t have to be your best berry picking spot, but you want to be sure it is a spot where the plants actually make a good number of berries in most years.

2. Collect 10 stems of lowbush cranberry (Vaccinium vitis-idaea) that have winter flower buds visible. Try to collect each stem one large step from each other, to get plants that are from a clone of each other. Put the stems in a ziplock bag.

3. Record the date of collection, your contact information, and a basic site description (latitude, longitude, slope, aspect, and dominant veg) on the datasheet.

4. Place the ziplock with the 10 stems and datasheet in an envelope. Please send them within a day or two of collecting. Samples do not need to remain frozen. Send the samples to:

Dr. Christa Mulder, Institute of Arctic Biology, University of Alaska Fairbanks, PO Box 757000, Fairbanks, AK 99775

What happens when I send in the buds? The buds you collect will be sent in batches to the Diggle Lab at the University of Connecticut to be dissected under a scanning electron microscope and their developmental stage will be evaluated. You will even receive your lab results, and a photo of a “prenatal” cranberry flower like the picture on the right! What stage of development will you buds be at? How do they compare with cranberry buds in other parts of the state?

How will the data be used?

This effort is part of a larger project funded by the National Science Foundation. The data from your buds and the buds of volunteers across Alaska will allow us to determine whether our results for the impact of environmental conditions on the flower bud development are representative of those from a much larger area. The data will be used alongside climate data to answer the question, “Can climate variables explain geographic variation in lowbush cranberry pre-formed bud developmental stage?”

These results will also be supported by observations of late-blooming flowers in the Local Environmental Observers (LEO) Network and an open top chamber experiment being conducted in the Bonanza Creek Long Term Ecological Research Station at UAF where some small woody plant species are getting artificially warmed and some are not to try to isolate changes in temperature as a mechanism for pre-formed bud developmental rates.

Your buds will be sent to UConn to be carefully dissected under a scanning electron microscope (SEM). This photo is a lowbush cranberry bud under the SEM. Photo by P. Diggle.