Trees can certainly be weedy, and in Florida we have a number of exotic invasive tree species which can be quite a problem. On the other hand, redbud is also native here, and it's possible that you have some natural ones (although the 8 ft/yr grown rate makes me doubt it).

Post a picture (if you can) of the possible weed trees.

define weed ...

a weed is anything that is growing where you don't want it ....

a weed is something that grows with great gusto .. regardless of the abuse the gardener gives it... like your trees ...

a weed is something that reseeds it self prolifically to the point of insanity .. its or mine.. lol ...

if you have free range seedlings.. you must have another redbud within a birds ability to spread it seed .... are there others in you area .... if not.. then you need to properly ID the plant that has self sown itself into your garden .... and then decide if they are 'weeds' or not ...

i had a redbud that died to the ground 3 winters in a row ... then.. apparently got a sufficient root mass to be considered 'established' and that thing grew 6 to 8 feet the next year ... and quit dieing down every winter ... your new tree most likely has not gotten 'established' .. and is struggling .. once it gets established... the growth rate will return to normal ...

good luck

ken

Maybe it's a cottonwood lol.
Similar leaves, right?

Check out Sapium sebiferum . . . that's one of Florida's worst weed trees.

Some others are Melaleuca, Casuarina, Ailanthus, Schinus.

Resin

Weed tree? BOXELDER a/k/a Manitoba Maple a/k/a Whatisthatuglything? a/k/a the trees that ate my yard. Native, but - seeds like mad, weak branches, coarse foliage, prodigious resprouting from stumps, terrible form as they lean to get the least bit of light, greedy shallow roots, lame fall color, attractor of its very own species of bug that congregates in droves on the side of the house (& the windows, & the screen doors...). No nursery would sell the straight species because no one with the least asthetic sensibilities would buy 1. Thanks for letting me get that out of my system.

"a weed is anything that is growing where you don't want it ....

a weed is something that grows with great gusto .. regardless of the abuse the gardener gives it... like your trees ...

a weed is something that reseeds it self prolifically to the point of insanity .. its or mine.. lol ... "

I'm with Ken. And I live in a place very inhospitable to most trees, the high plains, so just about anything that will grow out here is "not" a weed.

However, even here we get some species that have bad habits and aren't welcome. Salt willows (or whatever they call them ) that invade our small streams and steal water from our mountain streams and drinking water lakes, are a real problem and a weed.

Outside of that, most trees that are considered weeds elsewhere are well behaved and liked here.

Salt Cedar.

Mountain Cedars, which and bloom in Sourthern OK and Texas during the month of January.

OK, here I was THINKING that I had redbuds sprouting up all over the place, but could not understand how they were growing so fast, when the ACTUAL redbud is hardly growing and doesn't look good.

You guys are GREAT!!!
I think I've narrowed it down to (unfortunately) Chinese tallow (Sapium sebiferum) so that means it's a damn weed.

Here are links to the actual photographs I just took of these damn thing. Let me know what you think :) and THANK YOU everyone for all your great answers.

{{gwi:383938}}

{{gwi:383941}}

Yep, that's Sapium sebiferum, sad to say.

Resin

Chinese Tallow is the common name. Very serious catagory 1 invasive and should be removed instead of cultivated. There are other fast growing trees with nice fall color that can be used instead.

If you're just taking up an interest in trees in Florida this is just going to one of many disappointing discoveries. You have many great trees available but unfortunately some of the nastiest, most aggressive and damaging invasive trees in the entire US.