2 questions about our lawn

Question: To whom it may concern at MSU Agricultural Extension in Oakland County:

First of all, thank you very much for all that you do to try to help the residents of Oakland County with our lawn, garden, & farming problems & questions.

Secondly, every spring, after the snow melts, much of the grass in our front yard is brown & dead(?).  (Please see the attached photo IMG_1790.)  Grass plants turning brown & dead only occurs in the lawn on that side of our house, and not on the other three sides.  It also doesn't seem to occur in the lawns of any of our neighbors.  The one thing present in our front lawn (and not present in the lawns on the other three sides of our house, nor in the lawns of our neighbors) is our Imperial Locust tree (the tree in the foreground of IMG_1790).  Is there something in the roots of the Imperial Locust, and/or in its leaves (which cover our front lawn in the fall until we rake them up) which kills grass plants?  The thick dark green grass adjacent to our Imperial Locust may seem to contradict that hypothesis.  But the healthy grass growing there may be misleading.  We planted that grass (from Scotts' grass seed) just a few years ago.  So whatever species of grass that was in that seed may be resistant to toxins from our Locust tree's roots or leaves.

Thirdly, since we had so much brown dead grass in our front yard this spring, the first fertilizer that I applied to our whole lawn this spring was not "Scotts Turf Builder with HALTS Crabgrass Preventer", but "Scotts Turf Builder Green Max".   The grass plants on the other three sides of our house (i.e. NOT the side with the Locust Tree) seemed to green up a little faster than normal.  However, we now have a problem with Black Medic(?) growing in the grass on all four sides of our home, which problem I've never seen in our lawn before.  (Please see the attached photo IMG_1915.)  (Maybe the "Scotts Turf Builder with HALTS Crabgrass Preventer" was preventing it from growing in prior years.)  My questions to you about this problem are:
a) Is that Black Medic?  If not, what is it?
b) What herbicide (i..e. brand name) or herbicide ingredient (i.e. chemical compound) do you 
    recommend for killing that plant, but NOT killing the grass plants in our lawn?

Thank you for your answer to my first question (about what might be killing much of the grass in our front lawn every year) and for your best advice to my second set of questions (about the Black Medic[?] and how to kill it).

Gratefully yours,
Roman

responder: Dick M.  Replied July 19, 2023, 8:45 PM EDT
response: I did not find any information that the Imperial Locust tree produces toxins from roots or leaves that are harmful to turf. I'd start by doing a soil test on your front lawn to learn more about your soil including soil type, pH, nutrient levels and more. Knowing the type and fertility of your soil is the starting point to establishing & maintaining a strong turf that can resist diseases, moss and insects/grubs and look great. More info here: Don't Guess-Soil Test-MSU and MSU Home Soil Test-self mailer You state that the lawn is dead when the snow melts in the spring.  This points to possible pink snow mold or grey snow mold as the problem.  No way to tell now as the evidence is gone. Here  are links to turf diseases and their prevention: MSU Turf disease ID  Purdue turf disease ID Turfgrass Disease Chart-OSU  I'd reseed the front yard (after getting a soil test) making sure to stop fertilizing after Oct 1.  The best time to reseed is Aug15-Sept 15 and earlier is better.  Raking the leaves up is a good idea too or mulch them into the turf.  More info on reseeding in the attached links: Establishing A New Lawn Using Seed (E2910)-MSU Renovating A Lawn for Quality & sustainability-UMN How to Overseed A Lawn-Iowa Lawn Renovation & Over-seeding-UMass Renovation of Lawns-PSU  Yes the weed isBlack Medic:  This weed can be suppressed or controlled with various postemergence herbicides, particularly those containing dicamba, MCPP, and/or fluroxypyr.  There are products at the local big box store.  I recommend spot spraying over a full lawn application.  Get it done quickly before the black medic goes to seed.  Next spring go back to the fertilizer with pre-emergent for additional control. More links to general lawn care: Benefits of Slow Release Lawn Fertilizers-MSU Smart Lawns Tip Sheets-MSU  How to Choose & Apply Grub Control Products-MSU Mowing Lawn Turf (E0013TURF) - MSU Turfgrass Insects-Purdue

responder: The Question Asker Replied July 22, 2023, 5:08 AM EDT
response: Dear Dick:Thank you very much for the time & care that you took to provide me such detailed & helpful answers to my questions.  I greatly appreciate it.Gratefully yours,Roman SkikunNovi, MI On Wed, Jul 19, 2023 at 8:45 PM Ask Extension <<personal data hidden>> wrote:

responder: The Question Asker Replied November 02, 2023, 11:57 AM EDT
response: Dear Dick:I am the Novi resident who asked you in July if you might know:a) What might be causing so much of the grass plants in our front yard (with Imperial Locust tree) to be dead by spring?;b) What herbicide should I try to get rid of Black Medic?I tried your suggestion of using a herbicide with MCPP (specifically, Home Depot's "Vigoro Weed & Feed", with 0.6% Mecoprop-p & 1.2% 2,4-D), and it worked very well:  much of the Black Medic was gone in two weeks, and almost all of it was gone after a month or so. You also answered my first question, about whether Imperial Locust roots or leaves have toxins harmful to grass plants.  A while after your answer, however, I think that I may have figured out what is causing much of the grass in our front lawn to be dead by spring, and it's only indirectly related to Imperial Locust leaves.  I saw our problem (i.e. much of the grass in our front lawn being dead by spring) only in our front lawn (where we have that Imperial Locust tree), and in none of our other yards (which have no Imperial Locusts), and in none of our neighbors' yards (which also have no Imperial Locusts).  So, I assumed that this problem had something to do with that tree.  However, later this summer, I also noticed/remembered an area in our back yard which also had a lot of dead grass this past spring, and I realized what is common between that area, and our front lawn:  both of those areas were very strenuously raked the prior fall:- I strenuously raked our front yard last fall to try to pick up all of the Imperial Locust leaves' small leaflets;- I also strenuously raked that area in our back yard last fall to try to pick up the numerous leaves which had fallen & gathered there from our neighbor's back yard trees.So, maybe it's my strenuous raking which is killing the grass plants in those two areas.  I wanted to share this hypothesis with you in case anyone else ever contacts you with the same problem (areas of dead light-brown grass in the springtime, in a lawn where the other grass plants are just fine).Gratefully yours,Roman SkikunOn Sat, Jul 22, 2023 at 1:05 AM Roman Skikun <<personal data hidden>> wrote:Dear Dick:Thank you very much for the time & care that you took to provide me such detailed & helpful answers to my questions.  I greatly appreciate it.Gratefully yours,Roman SkikunNovi, MIOn Wed, Jul 19, 2023 at 8:45 PM Ask Extension <<personal data hidden>> wrote:

responder: Dick M.  Replied November 04, 2023, 11:21 PM EDT
response: Thank you for your follow-up comment on heavy raking your lawn.  I will keep it in mind as I answer future AE questions. I am attaching a link to an article on mulching leaves into your lawn and the benefits: Mulch Leaves into Lawn-MSU  The Benefits of Leaf Mulching-Cornell I have mulched leaves into my lawn for years with no detrimental results.

responder: The Question Asker Replied November 08, 2023, 12:02 AM EST
response: Dear Dick:Thanks for links to those articles, and for the info. on your experience with mulching leaves into grass.I spoke too soon when I sent that e-mail to you on Oct. 20, thinking that it might have been my strenuous raking which killed so much of the lawn in our front yard, and a small area of our backyard's lawn, by spring time.  When I started raking these areas a few weeks ago, I noticed that these same areas (as in the photo I attached in my Oct. 20 e-mail to you) had already started to become thinner & brown again, before I even raked them!  Maybe I do rake those areas too strenuously each fall, but that obviously can no longer be the cause of why those areas turn thin/brown/dead by spring time.  Something is just different about the grass plants in those areas.  I'll let you know if I have any further info. in the future, so that info. could help you to answer similar questions from others in the future.Thanks again for all of your help;Keep up the great work!Roman On Sat, Nov 4, 2023 at 11:21 PM Ask Extension <<personal data hidden>> wrote:

responder: The Question Asker Replied November 08, 2023, 12:02 AM EST
response: Dear Dick:Thanks for links to those articles, and for the info. on your experience with mulching leaves into grass.I spoke too soon when I sent that e-mail to you on Oct. 20, thinking that it might have been my strenuous raking which killed so much of the lawn in our front yard, and a small area of our backyard's lawn, by spring time.  When I started raking these areas a few weeks ago, I noticed that these same areas (as in the photo I attached in my Oct. 20 e-mail to you) had already started to become thinner & brown again, before I even raked them!  Maybe I do rake those areas too strenuously each fall, but that obviously can no longer be the cause of why those areas turn thin/brown/dead by spring time.  Something is just different about the grass plants in those areas.  I'll let you know if I have any further info. in the future, so that info. could help you to answer similar questions from others in the future.Thanks again for all of your help;Keep up the great work!Roman On Sat, Nov 4, 2023 at 11:21 PM Ask Extension <<personal data hidden>> wrote: