I have an "in general" (as opposed to wildflower expert) guess, Bski, based on 25 years of managing (OK, trying to manage) and observing pastures and hayfields.

The presence and success of (some of) the perennials will lower the overall annual impact from now on. Some of those annuals will do well in the conditions at LNP, and make a strong presence most every year. Some will be a lot scarcer from now on. Some will disappear.

Which flowers (annual or perennial) do the best can be modified by management practices (or incidental occurrences) like mowing schedule, fertilizing, disturbing the soil etc.

"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
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