To Waldemar and all,

There is no doubt that chasing the black locust bloom can be frustrating at best.  I have been currently examining this same problem in the last few years since having a huge locust bloom in 2005.

I hate to answer a question with a question but.....What was your weather like during 2006 and was it a year of abundant rainfall and ample growth or one of poor amounts of water and stress?

There is no question that there is much we don't know about the production of nectar in plants and I don't know of a single phloemologist or nectarologist and if there were any there would be much room for dissagreement on what causes good years and bad.
While having over 100 books and many years collection of ABJ and Gleanings there is really very little information on this subject.   I would refer you to chapter 10 of "The Hive and the Honey Bee" entitled The Production of Nectar and Pollen which may contain some of the answers.  Most who have Nut or Fruit bearing trees and shrubs know that our production this year is very heavily dependent upon last years conditions of ample water and stem production yielding heavy leaf set, maximizing the production and storage of carbohydrate for next years actual bloom.    On page 409 there is reference to D.U. Girnik who in 1958 used radioactive isotopes to determine that some of the nectar  secreted by Linden trees (Tilia spp.) came from stored carbohydrate.   During years of drought such as the last two in our area trees will drop a percentage of foliage and at times completely defoliate to conserve moisture.   This defoliation results in a decrease in tip growth due to a decrease in sugar production and storage.   Trees and shrubs will have less capacity to bloom ( less bloom buds) as a result.   
While not an expert in the matter, it would be my opinion that black locust bloom is highly dependent upon the last year and perhaps the last several years environmental conditions and not just available moisture, sunlight and temperature levels currently.   
Here in southeast Kansas we have extreme conditions and only find fairly dependable Black Locust bloom in areas where there is a water table.   I have 100 hives located two counties (75 miles) from my home where three major rivers exit Kansas and a shallow water table exists most of the time. It is a great pecan production area and yields black locust flows fairly consistently.  In 2005 I had 40 - 50 hives there and in one week they all packed out the deep honey super that I had on them and many filled much of the space in the brood chambers as well.  I drove back home and got another truck load of supers and put them on but after returning the week later found that while some were still blooming the flow had ended.   That smell that was so strong the week before and had been almost intoxicating was gone.

In reading Walt Wrights article, I would only have a couple of questions; 1. Do all of the hives in an apiary experience this "storage lull" at precisely the same time?   I know if I have 20 hives in an out apiary buildup among them will vary widely.   When there's a black locust bloom on, it seems that most healthy hives store nectar or they don't.  It would seem  more logical in my mind
to search for the answer in the cycle of the nectar source than the cycle of the bee colony.  2.  Why when I requeen every August, excepting those prolific queens in 15 - 20% of colonies do I see the storage lull in some and not others.  I have no doubt that this phenomenon exists, but I really have some doubts as to the correlation to the lack of a storage of black locust nectar.
This is an area we all need to know more on.
Hope this has been a bit of help in answering your question.
Tim Tucker

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