Maryland is a pleasant place to reside, especially due to their temperate climate with four different seasons.
However, hostile weeds can plague their gardens and lawns throughout the year. Even their best-manicured lawns can have these invaders at least once every year.
Weeds can pop up anywhere they get room among other grass or cultivated plants.
Seeds spread through wind or animals and sprout in the soil, producing roots. More significantly, their seeds can remain viable in the soil for years before sprouting.
These pesky intruders multiply rapidly.
So it’s necessary to take early action and care for your lawn or garden before they turn ugly. And in order to do this, you should identify the common lawn weeds that can let you experience sleepless nights in the beautiful temperate climate of Maryland.
Below is a list of the most common Maryland seeds to help you spot them easily and choose the best approach to get rid of them. So let’s take a look!
6 Common Lawn Weeds in Maryland
Worried about weeds in your lawn? Don’t be. Here are 6 common lawn weeds in Maryland to help you spot them before they can ruin your landscape.
1. Dead-nettle
| Scientific Name | Lamium amplexicaule |
| Family | Lamiaceae |
| Type | Annual broadleaf |
| Common Names | Dead Nettle, Purple Dead Nettle, Purple Archangel, Purple dead-nettle. |
Do you see light purple flowers nodding in your garden or yard? It’s possibly the dead nettle. The name perfectly signifies the deadly impact the weed has on the landscapes.
Dead-nettle is an annual winter weed that can turn an entire cultivated lawn into a reddish-purple field.
They tend to germinate in disturbed soils in gardens and areas. However, they can tolerate moist soils and moderate shade to full sun.
Although the name suggests, dead nettle isn’t a member of the nettle family and won’t cause skin irritation.
Instead, this weed belongs to the mint (Lamiaceae) family and resembles henbit. Young plants sprout soon after the seed germinates in the fall.
Seedlings live throughout the winter and mature quickly in the spring. Dead-nettle blooming pinkish-purple flowers in April and seeds start to appear in late spring. However, they wilt and die off when the temperature increases during summer.
Key Characteristics
Leaves grow on upright stems and stolons (horizontal stems) that develop along the ground, forming patches.
Interestingly, this weed’s leaves are considered dead and have no hairs. The key distinguishing feature is their square, four-sided stem.
Purple dead nettle features triangular-shaped leaves, and the upper surface is either red or purple. You will see the leaves clustered around the stem’s axis. However, the dried nettle’s leaves are an excellent poultice for hemorrhaging.
Another distinctive trait is their pink flowers, lasting nearly six weeks after blooming in April. Within this time, they produce four seeds that can give rise to a new plant.
Moreover, the tubular-shaped flowers bear the pollen and nectar enjoyed by bees.
Purple dead nettle can reach up to 30cm in height and 18cm in width. However, you can even find them short.
This weed reproduces by seeds. Therefore, the best time to control them with herbicides is during their active growth period or in the fall.
However, if the infestation is small on your lawn, you can pull them out quickly. Mowing will also be effective before seeding.
Also Read: Weeds in Indiana: Identify 6 Different Common Weeds with Pictures
2. Chickweed
| Scientific Name | Stellaria media |
| Family | Caryophyllaceae |
| Type | Winter annual |
| Common Names | Starweed, Passerina, Star chickweed, Birdweed, Starwort, Winterweed. |
This winter annual is another nemesis of Maryland gardeners that can pop up in any disturbed, overwintering field crops or cultivated horticultural gardens.
However, chickweed is hard to deal with, as it grows aggressively throughout the flourishing season. And plant parts can re-root if left on the ground.
Key Characteristics
Chickweed has seedlings with slender stalks and features oval-shaped cotyledons and sparse hairs. However, they have egg-shaped to rounded young leaves with pointed ends. The leaf is connected to the main stem via small stems nearly half the blade’s length.
Mature plants have closer to the ground. Besides leaves, stems are also light green. However, they exhibit oval-shaped leaves with pointed tips and a bit folded at the mid-vein.
You will also notice hairy petioles on most leaves, except some young leaves. Another key feature is their fibrous root system. Roots will grow wherever the stems reach the soil. The stems are fragile enough to detach from the roots, and new plants regrow after dragging them out.
Flowers continue to bloom on mature chickweed plants. Eventually, it becomes pretty challenging to manage a seed bank.
However, you will see small, white, five-petaled flowers sprouting from the leaf axils. Thanks to the profoundly lobed petals, flowers seem to have ten petals. On the other hand, chickweed has oval fruits bearing 8 to 10 seeds.
Note: Many of you may confuse common chickweed with mousear chickweed.
But you can easily differentiate between the two by looking at the leaves. The mousear variety doesn’t have the points of common chicken ones. In addition, the entire weed has dense hairs.
Common chickweed can germinate and produce seeds throughout the year. So it’s essential to implement control methods in every crop rotation phase.
3. Shepherd’s Purse
| Scientific Name | Capsella bursa-pastoris |
| Family | Brassicaceae |
| Type | Annual to biennial broadleaf |
| Common Names | Witches’ pouches, Lady’s purse, Shepherd’s sprout, and Shepherd’s scrip. |
Next on the list is this annual broadleaf that inhabits cultivated lawns and disturbed landscapes.
Shepherd’s purse is named after its unique, triangular seedpods. However, this weedy mustard’s star-shaped hairs make them easier to spot even before seed development.
Key Characteristics
The weed is characterized by its rounded egg-shaped cotyledons and purple to light green seedling stem.
You will see the first two to four leaves rounded and slightly toothed or untoothed margins. Moreover, the first two ones have star-shaped hairs and are opposite.
The subsequent leaves manifest alternate arrangements in a basal rosette. On the other hand, rosette leaves can be toothed, deeply lobed to mostly lobed with hairs on the lower leaves. Reversely, upper leaves are smooth or lightly haired.
When this weed matures, they develop slender and purple to green stems with grey hairs. The top is smoother and hairy at the base. The flowering stem can extend up to 7m tall, and you may find branches at the top.
Stem leaves are lance-shaped with no leaf stems (petioles) or lobing. Flowers appear during the spring and continue until early summer in clusters with a long spike.
New flowers grow at the top while seedpods form at the bottom. Moreover, they are characterized by four white petals and green sepals.
Their long and wide fruits contain a unique, heart-shaped or triangular, flattened pod that resembles a Greek shepherd’s bag and, thus, the name ‘Shepherd’s purse.
Apart from this, the weed has a recognizable branched, thin taproot system with secondary roots.
Shepherd’s purse has tiny seedlings, and it’s best to control them at this stage.
After that, you can opt for mechanical cultivation and tine-weeding. Another preventive approach would be cultivating competitive plants and rotating with summer crops.
You May Also Read: Spot 7 Different Types of Weeds in Mississippi
4. Black Medic
| Scientific Name | Medicago lupulina L. |
| Family | Fabaceae |
| Type | Annual or short-lived perennial broadleaf |
| Common Names | Black clover, Hop clover, Yellow Trefoil and Trefoil. |
A distinguishing characteristic of this weed is its crawling-growing nature. Black medic is an annual summer weed that generally loves compressed soils like roadsides. However, they are a common nuisance in lawns and gardens.
A fascinating feature is that this weedy plant has its nitrogen-fixing abilities being a legume. As a result, they can out pass turf in nutrient-less soils.
Together with their capability to endure low mowing heights, the black medic is a problematic weed to get rid of it in Maryland lawns.
These low-growing weeds spread aggressively and blend into a lawn, making them hard to spot. On top of that, the black medic is often confused with clovers with yellow flowers. But some key characteristics can help you to differentiate them easily. So let’s find out here!
Key Characteristics
This leguminous weed consists of nearly square, prostate, and low-growing stems propagating below the turf canopy up to 2 feet long. Once established, these stems can’t produce roots. Black medic sprouts from seed during early spring or autumn.
Moreover, a central, deep taproot characterizes this weedy legume. Apart from this, they feature flat green, trifoliate leaves on the top, toothed at the tip, and wedge-shaped and pale green below.
Black medic has leaf stem a bit longer than lateral leaves, which makes this weed different from white clover and oxalis. Small yellow flowers blossom in a tight, ball-shaped cluster from the spring until the fall.
The name ‘black medic’ comes from the cluster of black seedpods formed when the flowers mature.
Nevertheless, an effective way to reduce infestations is by ameliorating turf density via regular mowing, fertilization, and planting suitable turf grasses. However, post-emergence herbicides can also control or suppress the black medic.
Also Read: When to Apply Pre-Emergent Herbicide – Preemergent Weed Killer
5. Knotweed
| Scientific Name | Polygonum cuspidatum |
| Family | Polygonaceae |
| Type | Perennial broadleaf |
| Common Names | Wireweed, Doorweed, Matweed and Wiregrass. |
Knotweed was initially recognized for its beauty and regenerative abilities.
Today, this weed is popular as a pest species’ that can outclass native or cultivated plants, destroying the built environment. Knotweed has unique creamy white flowers appearing in clusters in late summer and early autumn.
Key Characteristics
Knotweed is often mistaken for dogwood and other common shrubs because of the amount of foliage production.
However, you can easily differentiate knotweed by its creamy white flowers, shovel-shaped leaves, and bamboo-like stems.
They have spade-shaped, green leaves with a pointed tip, displaying a zig-zag pattern. Unfortunately, this weedy plant doesn’t have leaves in winter.
On the other hand, the shoots are hollow and can develop up to 2cm daily. The crowns grow from dense clumps, and you will see prominent nodes between stems that give rise to new plants.
Seeds have tiny wings and are shaped like a heart, and they rarely germinate. Moreover, their roots are yellow or orange and dark brown on the outside. The roots can grow 2 to 7m horizontally and 3m in depth based on the weather condition and soil.
Your best bet to control knotweed would be a combination of herbicide application and cutting. You may need to carry out an early summer or late spring treatment followed by re-treatment during the early fall.
Also Read: 10 Types of weeds in Minnesota | Guide to Spot them
6. Hairy Bittercress
| Scientific Name | Cardamine hirsuta |
| Family | Brassicaceae |
| Type | Annual or biennial broadleaf |
| Common Names | Hairy bittercress, Land cress, Lamb’s cress, Spring cress, Shot weed, Hoary bittercress, and Flick weed. |
This annual broadleaf is a member of the mustard (Brassicaceae) family. Hairy bittercress prefers moist soils, shady areas of lawns as well as full sun.
They are usually cropped up in vegetable gardens and ornamental beds during early spring.
While bittercress belongs to the mustard family, it can appear as a summer annual, biennial, or winter annual. Seedlings come out after germination during the fall. And flowers usually bloom and produce seeds in the spring.
What makes bittercress unique and successful in invasion is their capability to knock their tiny seeds from their ‘seliques’ (casings). However, the seeds can stay dormant for several years.
Key Characteristics
Hairy bittercress has rounded cotyledons on long petioles with a hairy surface. The first two leaves are heart to kidney-shaped, and subsequent leaves appear with alternate leaflets.
Mature plant leaves even have a more prominent kidney-shaped terminal lobe.
However, leaflets have lightly or shallowly toothed lobed margins. The upper plant portion has hairy leaves on the upper surface. But you may not find hairy leaves on the basal plant side.
Hairy bittercress has angled, smooth, and branched stems. Flowers bloom from mid to late spring, forming at stem ends with seedpods at the lower ends of stems. When the seedpods mature, they open up, launching seeds from the plant.
However, flowers are composed of 4 sepals, four petals, and four stamens. And the fruit is like a flattened capsule.
So the most effective way to control this weed’s growth is by hand removal or tillage/cultivation. But try to control before they start setting seeds.
Conclusion
So these are some of Maryland’s most destructive and persistent weeds that are hard to eliminate and control. Besides the seed, you should eradicate the entire root system for efficient control. And control measures include physical, cultural, mechanical, or chemical techniques.
