Grassy Weed Identification

Question: I was hoping I could get some help on what type of grassy weed this might be. I live in Frederick county in Emmitsburg if that helps. I seem to mostly get on my all KBG side. I’ve only used certified weed seed after my reno, so not sure if it’s from the soil, animals, etc. But depending on what it is will depend on how I treat it. Also, my neighbor across street has a whole crap ton of it, so it might be the same thing and I could help him as well

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 April 15, 2024, 4:14 PM EDT
response: Grassy weed ID can be tricky due to small differences in physical features, especially from photos, but the traits we see suggest Orchardgrass, a common perennial cool-season grass. Management options are included in the linked page. Was any straw used to cover the seed last time the lawn was seeded/overseeded? Perhaps it had some weed seed, or as you suggested, maybe seeds blew-in from nearby yards if more Orchardgrass is growing there and its seed heads weren't mowed off before they matured.  Miri

responder: The Question Asker Replied April 15, 2024, 4:36 PM EDT
response: No, I did not use any straw nor will I ever use any straw for that very reason. I did bring in a mixture of topsoil, sand, compost when I did my renovation, and I used the highest quality certified Bluegrass seed that Mountain View seeds makes. I used their 365ss blend.  ----------------------------------- Jason

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 April 16, 2024, 12:10 PM EDT
response: Ok, perhaps it seeded-in from another yard or open space, then, when mature Orchardgrass went to seed. For the future, if you aren't already, we suggest you consult with the recommended turfgrass cultivars publication (updated every summer) that lists which varieties of each turf type have performed best in Maryland conditions. Overseeding in autumn with those will help keep the lawn vigorous and dense enough to out-compete most weeds on its own. (High quality seed is good to use too of course, but depending on how customized that supplier's blend was for mid-Atlantic or "transition zone" climate, it might not include varieties well-suited to our challenging conditions. Typically, we suggest MD lawns be comprised of a majority tall fescue and very little Kentucky bluegrass, unless someone is willing to have a high-maintenance lawn.)  Miri

responder: The Question Asker Replied April 16, 2024, 1:39 PM EDT
response: Well, fortunately, every single cultivar that I’ve used for fescue and Bluegrass are all on the proven list that you sent me below. Most of my turf is pretty thick, but the majority of where I have issues is around my tree where it doesn’t grow nearly as well and it’s really thin. I was wondering if adding dirt in that area would help grass be able to establish better.  CURRENT KBG GOOD AREA CURRENT KBG AROUND TREE ----------------------------------- Jason

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 April 16, 2024, 2:01 PM EDT
response: Great! We suspect the tree, both in terms of dappled shade and root competition, is what is causing thinning of the turf near it. Trees and turf don't mix over the long run (a healthy tree will win), so you might consider using fine fescue instead in that area, or replanting with alternative plantings (or just using mulch if you prefer). We would not suggest adding soil; too little won't do much, and too much (an inch or more) could either deprive the tree's roots of too much oxygen or cause them to grow more shallow as a result to compensate, worsening the issue with competition.  Miri

responder: The Question Asker Replied April 16, 2024, 2:14 PM EDT
response: So, even if that area is lower than the rest of my yard, it wouldn’t be a good idea to even put any topsoil there to cover the roots that are surfacing and at the same time filling in that hole to level my yard? Asking because i obviously see top of roots and assume hard or impossible for grass to grow/survive very well there.  Also, you’re saying I could use my fescue just in that spot and would grow better than the KBG? ----------------------------------- Jason

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 April 16, 2024, 4:14 PM EDT
response: Correct, adding soil atop established tree roots is not a recommended practice unless there is drastic erosion, in which case you'd just be replacing what was lost and not adding more. (That isn't the case here.) Roots can be very sensitive to soil oxygen levels, and the deeper the soil, the less oxygen available to roots, which use it for respiration (essentially to "breathe" so they don't weaken and succumb to root rot pathogens). Even an added inch of soil might have detrimental impacts on plant roots. Tree roots can grow more shallowly when they aren't getting enough moisture or oxygen (usually the latter), since its more readily available at the soil surface, so compaction from frequent/regular foot traffic will encourage roots to grow closer to the surface. Some trees are more apt to do this than others, like maple (looks like the tree type pictured), birch, magnolia, and beech, but any can do so if stressed or in heavier soils that compact easily (like clay). With turfgrass, core-aeration every autumn or so can help to alleviate some compaction, but this would risk injuring too many roots to attempt over the root zone of a tree.  Kentucky Bluegrass is much more disease-prone in partial shade (powdery mildew, rust, leaf spot, root rot), in addition to simply being less shade-tolerant overall compared to tall fescue and fine fescue. (Seed mixes for full sun tend to be tall fescue; seed mixes for semi-shade tend to use mostly fine fescue.) Even those two turf types have their limits with regards to shade, but a few hours of direct sun during summer can be enough to keep them in halfway decent condition if you aren't able to replace the turf with other species. Fine fescue needs different care than tall fescue, though (much less mowing, for one), so using tall fescue if you already have some might be the most compatible with the care for the KY Bluegrass.  Miri

responder: The Question Asker Replied April 16, 2024, 4:24 PM EDT
response: So tree roots can actually grow deeper or more shallow on their own? How does my other tree (Bradford pear) survive if I can’t even see its roots, which means they are covered by soil? ----------------------------------- Jason

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 April 17, 2024, 10:09 AM EDT
response: They can, but not once formed; that is, a two-inch-thick older root is not going to move shallower or deeper into the soil, but young growing tips of fine roots may wander up and down in the soil profile to find conditions that suit their needs. Seeking enough oxygen is one reason roots often develop in mulch "volcanos" (the way-too-much mulch piled against tree trunks that can be seen in many landscapes), since it's a dark environment that also gets a decent amount of oxygen. When the roots in that mulch run out of moisture, though, since mulch doesn't retain moisture to the same degree soil does, they can die off and stress a tree. Or, equally bad, they will circle around the trunk in that pocket of mulch, staying in the well-oxygenated zone, and as both the trunk and major roots increase in girth with age, the root "strangles" or girdles the trunk, eventually causing canopy dieback or even killing the entire tree.  It's normal to not see all surface roots on a tree (for example, the flowering pear). They can be covered with a few inches of soil if that's how they developed while they were growing. The vast majority of a tree's root system, regardless of tree species, will lie in the top foot or two of soil depth, radiating around the trunk outwards and reaching further out than the branches do (the edge of the canopy is called the "drip line.") The further out from the trunk, the finer the roots get, mirroring how branches form with thick bases attached to the trunk and smaller diameter the longer they grow. Some tree species simply have a predilection to growing shallow roots in more compacted or wet soils, so it's more likely a gardener will run into some surface-showing roots for maple, beech, etc., in yards with compacted soil conditions. In woods, where the soil is essentially undisturbed and not compacted from the house construction process and ongoing human foot traffic, the soil is much less compacted and tree roots don't need to react to lower-oxygen conditions by forming closer to the surface as they spread.  The inability of established tree roots to change position in the soil is the other reason why adding soil atop existing roots is not recommended -- they cannot compensate for the change in oxygen and moisture levels from added depth, so might suffocate (so to speak). Roots growing into the new soil after the fact, being new and still forming, can compensate by growing shallower again, into the soil layer with enough oxygen, but the original root they branch off of cannot move itself shallower.  It might help to think of it a bit like how branches on a tree or shrub canopy behave long-term if they get more light from one side than another, say due to an overhanging bigger tree or being crowded close to a wall or fence. The plant essentially leans into the more well-lit side, with branches preferentially growing in that direction to access the light they need. The roots do something similar -- in that analogy, the main branches aren't moving to get the light (they can't, they're too stiff with mature wood), but the leaves and new supple twig growth that they produce each season is what is changing the direction of growth (and for roots, their depth in the soil) over time to compensate for those changes in the plant's environment.  Miri

responder: The Question Asker Replied April 17, 2024, 10:36 AM EDT
response: Thank you for answering my questions! I know I’m rambling and being a pest, but grass is one thing, but plants/trees is one I’m still learning about and don’t want to screw anything up. On topic of trees in regards to fertilization.1. Do I need to add extra fertilizer to the maple we were talking about if I’m already fertilizing the lawn around it as well as running my in ground irrigation (if so how much)?2. How much fertilizer should I add to my dwarf Japanese maple, which is now in its second full season. I have not directly added fertilizer to it as it sits alone by itself in my flower bed, which I’ve been working on redoing (so I don’t have any flowers or mulch yet) - I have no idea what to add. Thanks!On Wed, Apr 17, 2024 at 10:09 AM Ask Extension <<personal data hidden>> wrote:

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 April 17, 2024, 11:55 AM EDT
response: Hi Jason,  No, a tree surrounded by lawn that is fertilized will rarely need fertilizer of its own. Even if it were to show symptoms of nutrient deficiency, contributing factors like root damage or improper pH (soil acidity) would need to be ruled-out first, since they would be a more likely cause. Only a laboratory soil test can determine if any key nutrients are deficient, and they also screen for pH level with more accuracy than a home soil testing kit or probe. Even if the tree weren't surrounded by lawn, fertilizer is usually not needed for established plants. (The soil usually has all the nutrients they need to support growth at its normal pace. Trying to force extra or faster growth with a nutrient boost can backfire by resulting in weaker (less sturdy) stems or a greater vulnerability to pest outbreaks or infection.)  As with the other tree, the Japanese maple should not need any fertilizer. Gardeners tend to think of fertilizers (and they are marketed this way, so we don't blame them) as plant "food," but that is not really accurate. Sunlight is more akin to plant food, and the nutrients they absorb from the soil support photosynthesis and growth. Fertilizer would be more of a supplemental multivitamin, filling-in for nutrients that are missing from a plant's "diet" (if the soil were deficient), but it cannot fuel growth directly without adequate other resources (sun, soil moisture, stored carbohydrates in the plant's tissues, etc.) and it cannot cure an ailing plant.  One of the better tactics to protect long-term plant health is to make sure trees are planted at the proper depth. We see what looks like the graft union swelling on the base of the J. maple trunk -- a normal feature that most will have because cultivars are usually grafted -- but can't make out enough detail to find the root flare. The flare is where major roots branch off of the trunk base, and it should sit just at the soil surface, visible and not buried by soil or too much mulch. You can learn more about how vital this region of tree structure is for root health in the linked page. Young trees don't always have an obvious flare as the structure's name implies, but it will still have that root junction that needs siting at the correct depth, and the flare itself develops over time as it ages. Keep it free of mulch and only put down mulch in a flat, even layer no thicker than 3 inches over the rest of the root zone. You can add companion plants if you prefer, but avoid putting in annuals that require yearly replanting since this repeated digging into the maple's root zone may cause damage or plant stress in future years. Perennials that don't need replanting because they live for many years are the better option in that regard.  Miri

responder: The Question Asker Replied April 17, 2024, 12:13 PM EDT
response: I had no idea about any of that with the trees and as of recently just learned about putting mulch in a “volcano.”    As far as pH my lawn is around 6.8-7.0 and am not deficient in any of my macronutrients. Not sure exactly what it is in the flower bed as I’ve never tested that before.    Here’s a better look at my trees roots. First image will be the Japanese maple, which I planted and the bigger maple was here when I moved in 2020 (but house was built in 2005, so guessing it was planted then).   JAPANESE MAPLE IN FLOWER BED  ORIGINAL MAPLE IN TREATED YARD  ----------------------------------- Jason

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 April 17, 2024, 12:44 PM EDT
response: We didn't receive the second photo for some reason, but for the J. maple, we can't quite tell if the bulge is the top of the root flare, a graft union, or a portion of a girdling root that developed when the tree was younger (before it was sold, probably). You might want to gently excavate more to see if you can find a clearer root junction. If not, this depth may have to suffice, as long as mulch isn't put over top of it (the trunk base that is, the rest of the root zone is fine to mulch).  That lawn pH is fine as-is, though slightly lower might be ideal (no need to try changing it at this point, since it's still within the acceptable range).  Miri

responder: The Question Asker Replied April 17, 2024, 12:55 PM EDT
response: Not sure why the other picture didn’t come through, but these are the pictures of the maple in my front yard.      ----------------------------------- Jason

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 April 17, 2024, 1:53 PM EDT
response: The error on our end shows that the file sent was too large (it did not come through this attempt either). It might need to be less than 8MB per file, in case your image was larger.

responder: The Question Asker Replied April 17, 2024, 2:29 PM EDT
response: -----------------------------------  Jason

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 April 17, 2024, 4:21 PM EDT
response: Got it that time, thank you. It looks like there might be at least one girdling root present, but it's hard to tell. Otherwise, the root flare exposure appears to be good as-is. If you wanted to pursue a diagnosis, especially if the tree has been showing signs of stress in prior growing seasons (like a declining canopy), hiring a certified arborist may help reveal any potential problems. They can use a tool called an air spade to remove soil without cutting roots, but its is loud and may be expensive, depending on the size of tree being "excavated."  Miri