Weed Identification

Question: Hello,

I'm having trouble identifying this weed. I believe this may be because the weed is so young. I went on vacation a week ago with no sign of this weed and came back today to find it growing everywhere I planted new grass. I'm trying to determine how best to remove it. I'm wondering if 4-Speed XT would be effective on it (but I'm a little worried about spraying a herbicide so close to the ~2 year old Emerald Green Arborvitae).

Thanks!
Eddie

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied May 23, 2023, 11:02 AM EDT
response: Hi Eddie,  These are seedling maple trees (possibly Red Maple, Acer rubrum), and they just germinated, which is why you didn't see them before. All they need is one or two mowings as you normally care for the lawn -- nothing special -- and they will die out on their own because they can't tolerate losing that much growth being that young. Herbicide would be overkill in this situation and we're not recommending its use because it's not necessary.  Miri

responder: The Question Asker Replied May 23, 2023, 4:58 PM EDT
response: Hi Miri!!  O wow, didn't expect it to be a tree! I believe my neighbor's tree is actually a red maple so that makes sense. Just kinda surprised how well the tree spread it's seed haha  Because the red maple is growing mostly in my new grass (less than 1 month old), would it be better to use a herbicide or just wait to mow it as you suggest? I'm worried the red maple will crowd out the new grass and take sunlight/nutrients/water from the new grass.  Thanks! Eddie

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied May 24, 2023, 11:52 AM EDT
response: Yes, maples are notorious for having prolific baby seedlings popping-up underneath or near female trees (maples produce male and female flowers on separate trees, so only female-flowered trees are the ones that produce seeds once they are pollinated). We routinely see them in lawns in springtime and they succumb easily to mowing and are not a season-long nuisance.  Herbicide is overkill here and not needed for this situation. During the brief time these seedling trees will be growing between being mowed once or twice before they die out, they will not substantially deprive the turfgrass of too much light, moisture, or nutrients. Herbicides can have ecological consequences and may stress non-target plants (the targeted plants being the weeds the product is being applied to control) so their use, as with any pesticide, should always be limited to when it's greatly needed to manage a problem that isn't easy to remedy using other means. The product you mentioned is particularly one which we would advise caution in using because it appears to contain four different herbicides (that's a lot, most use one or two...maybe three) and some of them might be risky to use around desirable plants. (The active ingredient dicamba, for instance, may harm tree and shrub roots and cause serious and lasting damage to the plants if they are over-exposed to an application.)  Miri

responder: The Question Asker Replied May 24, 2023, 10:20 PM EDT
response: As usual Miri, thanks for all the advice and details in the explanation, much appreciated!!! It looks like I'll have to look into how trees reproduce to fully understand your explanation haha

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied May 25, 2023, 2:06 PM EDT
response: You're welcome.