Question
QUESTION: Dear Mr Hyland

Thank you for your help! I'm really puzzled. Having chopped down our yellow mimosa tree two years ago, we've been inundated this summer with thousands of seedlings on our little lawn. They've grown not only on the lawn but also hundreds have done so from any visible roots of the tree that grow across the surface of the lawn.

They have been a real headache for months! Then two weeks ago they completely - and I mean completely - stopped appearing. Can we expect them back any time soon or are they 'done'?

Thank you so much for answering,
Yours sincerely,
Charlotte

ANSWER: A parent tree will sprout new growth when it is cut (especially hardwood specie). The sprouting will go on as ling as the root system is alive. When the roots die the sprouting will stop. I would guess that the root system as expended all it energy and the sprouting has stopped. I would not expect it to return next spring.

---------- FOLLOW-UP ----------

QUESTION: That's great and many thanks indeed for your help - but what about the seedlings, mentioned in my original email, that are not attached to the root but are growing on the lawn from seeds (seeds from pods)? Do Mimosas have particular months of the year when they germinate and sprout? The stopping has been so sudden that I am flummoxed.

Thank you,
Charlotte

Answer
Yes they do sprout from seed and these young plants if mowed will usually die and since there is not a source left for new seed the sprouting will stop. I would think that is what happened in your case. All the viable seed have sprouted and now there is none left to sprout. You should not see any next year.