Wildflower monitoring at botanical gardens

By Richard B. Primack

“To him who contemplates a trait of natural beauty no harm nor disappointment can come.” Henry David Thoreau in Natural History of Massachusetts. 

The phenology of wildflowers has been comparatively neglected in climate change research.  While researchers have extensively investigated the flowering times of wildflowers, there is surprisingly little information on their times of leaf out, leaf senescence, and fruiting. 

Primack monitors flowering times of marsh marigold.

In a recent article published in Functional Ecology, researchers describe the PhenObs initiative for making standard phenology observations on 199 wildflower species at four botanical gardens in Germany. The goal is to develop a protocol which could then be widely applied to wildflowers, and be used in both functional ecology and climate change research. 

Just a single date of flowering time needs to be recorded for bloodroot, rather than more detailed flowering stages.

Researchers recorded information on the dates of 14 stages of phenology involving leaf out, leaf senescence, flowering and fruiting. Analysis showed that these stages were highly correlated, so gathering such detailed information was not needed. The final recommendation is that for monitoring large numbers of species the dates of just five stages should be monitored: three stages of vegetative growth (initial growth, leaves unfolding, and leaf senescence), flowers open, and ripe fruits. 
 
This paper was published as:
Nordt, B.... R.B. Primack et al., 2020. The PhenObs initiative — A standardised protocol for monitoring phenological responses to climate change using herbaceous plant species in botanical gardens. Functional Ecology 35: 821-834. 

Link to Article