Hi HB,
In case you are interested.
Based on our leaf-out phenology model, temperatures to date this year, and the 10-day forecast as of
24 April 2019, our predictions for leafout on the Main bird plot:
Budburst = 11 May,
90% completion of leaf expansion = 24 May.
More details in pg 2 of enclosure.
If the budburst date is accurate, it will be about 3 days earlier than expected based on the 60-year trend (page 1 in enclosure).
Matt