How does Beech Bark Disease affect mast production?

[Lewis E. Ward]

     When does  Beech Bark Disease severly affect beechnut production? Has there been research on this?

     Beech nuts are/were a major source of mast in New England and NY forests. Of course, the production has to be averaged over the 5-7 years cycle of fruiting.

Here is the discussion I started by email. Please add your experience and and any research/references would be appreciated.

Response from Brett Chedzoy

    I’m not aware of any “research” done on crown decline vs. nut production.  Anecdotally, I’ve observed beech that seem quite impacted (bark-wise) from BBD, but that still have relatively healthy looking crowns – and visa-versa.  I suspect that nut production in beech is determined in large part by crown vigor, and that nut production is limited (or absent) once it falls below a threshold level.  -- Brett

LEW-

   Thanks Brett, I use to review the literature on mast production of oaks etc from the USDA's work up through the 80's. Most of the research is from the mid-south Missourri-Tennessee-Vigrinia-WV as I remember Don't know if much has been done since.

Would be intersting to see what Steve Gabriel can find and present at the Winter Seminar (February 22, 2014) of the Southern Finger Lakes Chapter of NYFOA

Response from Jeff Joseph

   
      Just based upon my personal experience, I would say that the scale-nectria has to be contributing to reduced beech mast, probably in combination with the fluctuating spring weather (late frosts) more often than not in recent years. Beech is basically all I cut for firewood (and have done so for 10 years running now), so I have gotten the chance to see the crowns of hundreds of trees of a variety of age/size classes, and I have almost never found a viable nut (a fair amount of husks of unpollinated or aborted seeds though). Everything I have read suggests that beech in the past would produce massive amounts of mast---enough to feed hungry bears, millions of passenger pigeons, etc......This is clearly not happening anymore, at least not in my woodlot. There's certainly enough pollen to go around, as I've got a lot of beech here.  As to Brett's observation, a good percentage of the beech I have felled over the years have been dominants which (despite the nectria) had big healthy crowns, and yes, I absolutely agree that a stem that is quite ravaged by BBD can still support a full and healthy looking crown, surprisingly enough.  ---Jeff

Response  from  Pete Smallidge

    

    Sorry to be late to this discussion. 

    I am not aware of any research that connects BBD to nut production.  I agree with observations by Brett and Jeff.  I note striking and almost complete annual production variation in that some years are bumper, most years are close to zero, and otherwise it is a weak partial crop.  Other than in bumper crops the nuts are often missing from the husk. 

The BBD will likely have a further impact related to tree longevity.  By analogy I note that oak doesn’t really begin good nut production until it reaches about 16 inches.  If beech, same taxonomic family, behaves similarly, then the likely of death by BBD prior to the tree attaining a larger size reduces the potential for significant nut production.  --- Pete

[Kevin Mathers]

I found this re: beech mast production in a Unv. of NH resource "Beech trees begin heavy nut production at about 50 years or 8 inches in diameter at breast height (DBH) and produce good crops at 2- to 8-year intervals".  So, they may produce mast earlier than oak, but Pete's point about retention of larger trees is still very valid.  Dominant or co-dominate beech seem to be very rare from my observations.