Looking at the early results, I have found that populations and families share several features, showing that genes are playing a role. Generally, plants from eastern populations had longer, thicker, broader forms than plants from western populations. Needles were significantly longer and broader in plants from southern populations. In the future I’ll be making further trait measurements, recording the timing of certain life events like cone production and measuring differences in biochemistry. These genetic differences tell us that plants have adapted to different local environments, and give a clue as to how.
We can also look at DNA directly. From each of the sixteen populations, small amounts of foliage from several trees were gathered. The extracted DNA from the foliage provides a unique DNA fingerprint for each tree. Using these data I can ask if populations are interbreeding today, and answer questions about ancient movements of juniper through the landscape. I am also working to team up with collaborators to make more collections of juniper from other parts of the UK, Europe and around the world.
Getting her hands dirty
Encouraging the natural regeneration of populations would help avoid some of the risks associated with planting from nursery stock or translocating juniper from one population to another. In a third strand of my research, I spent several long days lugging fencing around hillsides and digging through tough grasses to set up seed plots. Over the next few years, these will let me test how soil water content affects germination and survival of local juniper seeds.
It’s been an odd start to my first year of PhD studies – and with a steep learning curve – but happily I’ve got lots of work underway now. Soon we will know a lot more and be well on the way to protecting our juniper trees.