Minggu, 30 Agustus 2015
New Insecticide Labels to Increase Focus on Pollinator Protection
Weed of the Month for August 2013 is Common Bermudagrass
Common Bermudagrass
Biology: Common bermudagrass (Cynodon dactylon) is the most commonly used turfgrass in the southern United States, but it is also a difficult-to-control weed in northern turf. Bermudagrass is a drought tolerant, warm-season, perennial grass species that tolerates low mowing and actively spreads vegetatively by both rhizomes and stolons but also has the ability to spread by seed.Stolons of bermudagrass are visible creeping over a street curb. |
Bermudagrass rhizomes are thick and can be found in the soil. |
The patches are easily noticed in the summer months when cool-season turf is stressed by heat or drought. Patches are also noticeable in the early morning as bermudagrass holds a heavy dew on its leaves in the early am. In the winter months, bermudagrass is apparent as brown, dormant areas of turf.
Green bermudagrass is apparent in this drought stressed cool-season turf. |
Green bermudagrass is apparent in this drought stressed cool-season turf. |
Heavy dew on a small bermudagrass patch. |
Green cool-season turf surrounding a dormant bermudagrass patch. |
- Control before seeding or sodding an area during renovation
- Control for homeowners
- Control for professionals
- Professional products that contain fluazifop only that can be used during renovation include Fusilade II and Ornamec.
- Homeowner products that contain fluazifop only that can be used during renovation include ORTHO GRASS B GON GARDEN GRASS KILLER
For more information on weed control, search this blog and archived turf tip postings and check out our Turfgrass Weed Control for Professionals Publication.
Words You Might Hear a Turf Nerd Use
To help increase your turf nerd quotient (only nerds use words like quotient), I thought I would educate you about 12 words that you might hear a turf nerd use. Try your best to weave one of them into a conversation this week.
12 Words You Might Hear a Turf Nerd Use:
agrostology – the branch of systematic botany that deals with grasses2. Some of the first turf scientists in the country were first called agrostologists in the early 1900s.
anaeraobic – the absence of molecular oxygen2. This term is usually used when discussing soils. A soil that is anaerobic is lacking on oxygen. A wet or water-logged soil is anaerobic. Without oxygen in the soil plants suffer and shifts in bacterial populations occur.
apomixis – the laymen’s definition is “clonal reproduction through seeds” which is also known as agamospermy. This one gets complicated, but all you need to know is that Kentucky bluegrass is apomictic which means that when you buy a particular cultivar of Kentucky bluegrass (Poa pratensis), all the seed you plant will essentially grow-up to be genetically identical to the parent plant. With many other cool-season turfgrass species, the individual seeds are produced through sexual reproduction (intercrossing) of plants with similar traits which results in individual plants within a cultivar that are almost identical or very similar but technically genetically different than one another. Vegetative apomixis can also occur such as with bulbous bluegrass (Poa bulbosa).
cation – a positively charged ion2. Examples include calcium (Ca), magnesium (Mg), sodium (Na), and hydrogen (H). These will commonly be referred to as cations on a soil test report. Cation exchange capacity is a measure of the soils ability to retain these positively charged cations on the soil colloid which is negatively charged.
desiccation – the process of being desiccated (which is to dry up) due to the deprivation (another nerdy word) of water2. Desiccation or drying out is a common term used to describe a specific type of winterkill than can occur in turf when no snow fall is present and when wind speeds are high and windy days are frequent. Desiccation injury to turf is more common in the plains in states such as Nebraska.
dioecious – having staminate and pistillate flowers on separate plants2. A plant that has separate male and female flowers that usually occur on separate plants. Buffalograss is an example of a turf that is dioecious.
Male flower |
Female flower or burr. |
glabrous – having a smooth surface, without hairs2. When you want to describe that a grass plant is smooth and without hairs, use the term glabrous. The Kentucky bluegrass had a glabrous leaf blade. The opposite is pubescent which means covered with short hairs3.
hygroscopic – readily capable of absorbing and retaining water from the atmosphere, under normal conditions of temperature, pressure, and humidity2. You all have experienced this phenomenon whether you know it or not. Most fertilizers are hygroscopic. When you open the fertilizer bag and then come back a few weeks later and all the fertilizer is stuck (caked) together, it is due to the fertilizers hygroscopic nature.
marcelling – A wavy or washboard pattern on the surface cutting plane of mowed turfgrass; usually results where the clip of the reel exceeds the mowing height4. Marcelling is specific to reel mowers and not an effect seen with rotary mowers.
Look for the parallel lines running NNW. This is Marcelling. |
mat – Thatch intermixed with mineral matter that develops between the zone of green turf vegetation and the original soil surface; commonly associated with golf course putting greens that have been topdressed2.
rachilla – subdivisions or branchlets of the rachis that support individual flowers, (seeds), within the spiklet of grasses2. The axis of a grass spiklet3. This is the little golf tee looking appendage on a turf seed.
verdure – the quantity of green living plant tissue per unit land area remaining above the soil following mowing at a specified height and usually expressed on a dry weight basis2. Essentially, this is how much turf is left above the soil surface after mowing. We often measure the mass or the quality (carbohydrates, mineral content, etc.) of verdure in turf research.
I hope you enjoyed this post.
Aaron Patton, Turf and Weed Scientist, Purdue University
Footnotes:
- http://dictionary.reference.com
- From or adapted from Beard, J.B., and H.J. Beard. 2005. Beard’s Turfgrass Encyclopedia for Golf Courses, Grounds, Lawns, Sports Fields. Michigan State University Press, East Lansing.
- Harris, J.G., and M.W.. Harris. 2001. Plant identification terminology: an illustrated glossary. Spring Lake Publishing, Payson, UT.
- Turgeon, A.J. 2008. Turfgrass Management. Pearson Education, Inc. Upper Saddle River, New Jersey.
Sabtu, 29 Agustus 2015
Watering Bans Making Turf Establishment Tough in Some Locations
While turf can be established in the spring from seed, spring seeded lawns often perform poorly in the summer because 1) weeds like crabgrass also germinate in the spring and compete with turf seedlings, and 2) turf planted in the spring is shallow rooted at the start of summer and requires additional summer watering to keep spring seeded areas from succumbing to summer heat and drought. Thus, fall is the best time to seed a lawn and establish a lawn to reduce future watering needs and reduce erosion.
While water restrictions in Noblesville were lifted recently a water ban still exists in the city of Bloomington and the City of Indianapolis including Marion County and its surrounding communities.
The City of Bloomington and the City of Indianapolis water bans prohibit installing sod in damaged areas and new construction. While the optimum planting window for sod is slightly longer than the seeding window, early fall is still the best time to install sod. This helps promote long-term survival and fall rooting which in turn will reduce watering needs the following summer.
The City of Bloomington and the City of Indianapolis water ban does allow for watering new sod and newly seeded grasses, but only if these areas were installed prior to the watering bans going into effect. We would encourage the City of Bloomington and the City of Indianapolis to consider allowing exemptions this fall for planting seed or sod in turf areas damaged by this summer’s drought. This will help long-term turf survival, reduce soil erosion, and reduce 2013 watering needs.
2013 Imprelis Update: Tree Maintenance, Replacement, and Disposal
2013 Imprelis® Update: Tree Maintenance, Replacement, and Disposal (PDF) (08/13)
For a complete review of the facts and a more detailed description of the problem, see “A Turf Professionals Guide to Suspected Imprelis® Herbicide Injury in the Landscape” and “Imprelis Update: 2012 Field Notes on Injury and Recovery” available at our Imprelis Clearinghouse Website.
Aaron Patton, Turfgrass Extension Specialist, Purdue University
Jumat, 28 Agustus 2015
Weed of the month for August 2014 is Prostrate Spurge
Prostrate Spurge
Biology: Prostrate Spurge (Euphorbia humistrata) is a summer annual broadleaf weed that can be found in dry/sandy and/or nutrient-poor soils along with compacted, weakened or disturbed turfgrass and landscape sites. Look for it first in driveways and sidewalks or in potted plants in a landscape or nursery as temperatures start to get warmer. Prostrate spurge can also be found in cultivated fields, brick walls, and parking lot cracks. It germinates from seed in June and July in Indiana and spreads via low-growing prostrate stems than form a dense mat as they invade the turf canopy. Its ability to establish and grow in multiple soil/climate conditions and highly compacted soils, as well as its ability to withstand low mowing heights, make prostrate spurge a common turfgrass weed throughout the state of Indiana.The leaves of prostrate spurge are pale green, hairy, egg-shaped, widest at the apex, and located opposite of each other on the stems which are pinkish in color and distinctly hairy. Prostrate spurge continually flowers from July to September and produces large quantities of viable seed throughout its life cycle. These flowers are small but numerous, originate from the base of leaves located on the upper-stem, and are composed of several male and female flowers within a cluster. It produces a fruit that consists of a 3-lobed, 3-seeded capsule with stiff hairs on its surface.
Prostrate spurge is very difficult to distinguish from other spurge species, particularly spotted spurge (Euphorbia maculata). In fact, some taxonomists consider the two plants to be the same species. An identifying characteristic of both species is a small reddish-brown splotch at the mid-vein/base of the leaves which acts almost as a camouflage; thus, making the weed difficult to distinguish from the desired turf. The primary difference between these two species is that spotted spurge leaves are often darker in color and the nodes do not produce roots when they come into contact with the soil.
Additionally all spurges exude a milky/white sap when damaged that can be toxic to animals if ingested.
Once spurge germinates, control in cool-season turf can be achieved with applications of two- or three-way mixtures of 2,4-D, dicamba, MCPP, or MCPA which are available in multiple product formulations at local retailers. Repeat applications may be necessary due to the germination of new seedlings.
For more information on weed control, search this blog and check out our Turfgrass Weed Control for Professionals Publication.
For archives of past weed of the month postings, visit our Weed of the Month Archive.
Aaron Patton, Turfgrass Extension Specialist
Kamis, 27 Agustus 2015
New Publication: Calibrating Ride-on Sprayers and Spreaders
Calibrating Ride-on Pesticide Sprayers and Fertilizer Spreaders: Keys to Application Accuracy (PPP-104)
Aaron Patton, Turfgrass Extension Specialist, Purdue University
Fred Whitford, Coordinator, Purdue Pesticide Programs
Minggu, 23 Agustus 2015
Dr. Cale Bigelow Sabbatical
Selasa, 18 Agustus 2015
Plant Turf Seed or Control Weeds First?
Cool-season turf seed mixture. |
Option 1 for areas with mainly broadleaf weeds and a few annual grasses: Plant now and control weeds later.
The optimum time to control perennial broadleaves and germinating winter annual broadleaves is in October. As such, seeding in late August and early September should allow enough time for seeds to germinate, grow, and be mown twice (assuming you irrigate and fertilize these newly seeded areas) prior to an October herbicide application. You can delay the herbicide application until late October and early November if you get a late start on seeding or if your seedlings are slow to establish (like Kentucky bluegrass). Most broadleaf herbicide labels suggests delaying application until newly seeded areas have been mown twice. Some herbicide labels allow a shorter interval between seeding and an application. These shorter interval herbicides include Quicksilver, SquareOne, and Drive (shorter interval tall fescue compared to perennial ryegrass and Kentucky bluegrass).
Typical language about postemergence herbicide application delays after seeding turf. |
Drive XLR8 label instructions regarding application timing and seed and seedling emergence. |
Option 2 for areas where you have lots of weed competition: Spray weeds now and seed tomorrow.
When there is a lot of crabgrass or broadleaf weed cover, then you would likely benefit from spraying the weeds now and seeding afterwards. Tenacity, Pylex, and SquareOne, and Drive are among the herbicides that can be applied today and allow seeding as soon as tomorrow (after the herbicide has had a chance to translocate in the target weed). Once the turf germinates, then follow the guidelines in option 1 above to provide follow-up weed control if needed.
SquareOne application instructions allowing seeding one day following the herbicide application. |
Option 3 for areas perennial grassy weed competition: Spray weeds now and seed later.
When there are a lot of perennial grassy weeds such as quackgrass, fountain grass, etc., then your best bet to remove these perennial grasses before you seed as there are few herbicide options afterwards.
Best results with a non-selective herbicide like glyphosate are seen on perennial grassy weeds when multiple applications are made. Ideally, you would have started this process several weeks ago. Why? It is not uncommon for the weed to regrow from stolons or rhizomes (if a spreading grass) a few weeks after the first glyphosate application. One must allow the weed to regrow (wait at least three weeks) before the next application. At least two applications are recommended, but three or more may be needed. One must realize that the area will be dead and unsightly for a number of weeks or months if optimum control is desired.
Starting this process now, means that you won’t be able to seed until after the optimum seeding window of August 15 to September 15. If you are still committed to renovating this year, another seeding option is to seed in December through March as a dormant seeding after you have finished killing your perennial grassy weeds. Learn more about dormant seeding by clicking here.
If there are only a small number of patches, spot applications can be made with glyphosate. Reseeding can take place a day or two following final herbicide application. Once the area has been infested with a large number of patches, killing the entire area will be most effective with multiple applications of glyphosate. Renovation can begin five to seven days following final glyphosate application. Refer to AY-13, “Lawn Improvement Programs” for information on reestablishment.
One caveat to the above, Option 3 recommendation, is that we have a few selective herbicides for perennial grassy weed control that might be options for use during turf renovation.
Table 1. Non-selective and selective herbicide options for controlling perennial grassy weeds in cool-season turf.
Weed in cool-season turf | Non-selective herbicide option | Selective herbicide option |
Bermudagrass | glyphosate | Pylex (topramezone), Acclaim Extra (fenoxaprop) |
Creeping bentgrass | glyphosate | Tenacity (mesotrione) |
Dallisgrass | glyphosate | No effective selective control |
Field paspalum | glyphosate | No effective selective control |
Fountain grass | glyphosate | Drive (quinclorac) and other quinclorac containing herbicides |
Nimblewill | glyphosate | Tenacity (mesotrione), Pylex (topramezone) |
Orchardgrass | glyphosate | No effective selective control |
Quackgrass | glyphosate | No effective selective control |
Rough bluegrass | glyphosate | Velocity (bispyribac-sodium) for golf courses and sod farms. |
Tall fescue | glyphosate | No effective selective control, formerly Corsair (chlorsulfuron) |
Windmillgrass | glyphosate | Tenacity (mesotrione) |
Zoysiagrass | glyphosate | Pylex (topramezone)(based on preliminary results following labeled instructions for bermudagrass control) |
With any of these options, it is especially important to read the herbicide label and understand the application restrictions both before and after seeding and other application instructions (such as adjuvant and timing recommendations) so that you can maximize weed control and maximize turfgrass establishment.
For more information on weed control, search this blog and check out our Turfgrass Weed Control for Professionals Publication.
Aaron Patton, Turfgrass Extension Specialist
Fescue. You mean there’s more than one kind?
Bill: What kind of grass do you have?
Bob: Fescue.
Bill: What kind of fescue?
Bob: You mean there’s more than one kind?
Bill: Yes.
As I travel around the region and give presentations or respond to email and phone questions, it is very common for me to enter into a dialogue with a person about planting, maintaining, controlling, etc. some kind of fescue. Usually in my interactions with people, they are unaware that there are many different kinds of fescues.
Festuca is the genus (first word in scientific name) for fescue species. Hence, Festuca’s are name Fescue. However, recently tall and meadow fescue were reclassified by scientists into the genus Schedonorus (see table below) although they still retain their same common name of fescue. Tall fescue and meadow fescue are similar with meadow fescue being used sparingly for overseeding in warm-season turf or as a forage grass and tall fescue commonly being used in lawns, roadsides and pastures. The remaining fescues including slender creeping red fescue, strong creeping red fescue, Chewings fescue, sheep fescue, blue fescue, and hard fescue are often grouped together and called “fine fescues” because of their narrow (fine) leaves. Another reason for grouping them all together is because they are difficult to distinguish from one another. Blue fescue is another fine fescue species used as an ornamental landscape grass.
Below is a breakdown of the common (and a few not so common) fescues used in turf (and ornamentals) and a short description of each.
Table 1. Description of the common and uncommon fescues used in turf (and ornamentals).
Common name | Species | Comments |
Slender creeping red fescue | Festuca rubra ssp. littoralis | Similar to strong creeping red fescue but with shorter, more slender rhizomes. Both slender and strong creeping red fescue tolerate some close mowing. |
Strong creeping red fescue | Festuca rubra ssp. rubra | Strong creeping red fescue has more rhizome growth (spreading ability) than slender creeping red fescue. Strong creeping red fescue is a common ingredient in “Sun & Shade” mixes because of its good shade tolerance and its suitability in seed mixtures. |
Chewings fescue | Festuca rubra spp. fallax | Named after George Chewings. Excellent shade tolerance and turf density, this fine fescue is similar to creeping red fescue but it lacks rhizomes. |
Tall fescue | Schedonorus arundinaceus (Schreb.) Dumort. (also = Lolium arundinaceum (Schreb.) S.J. Darbyshire; formerly = Festuca arundinacea Schreb.) | Improvements in tall fescue have transformed this grass from a forage type grass to many improved turf-type cultivars. Today, both "forage" and "turf-type" tall fescue are used. Kentucky-31 (KY-31) is a forage type and not a lawn type. Known for its ability to maintain green color during moderate droughts due to its deep root system, tall fescue is more commonly used today on lawns than in the past. |
Sheep fescue | Festuca ovina | Excellent drought tolerance. This fine fescue with fair turf density does not tolerate close mowing. It is often used in unmown, “native” areas of golf courses. |
Blue fescue | Festuca glauca | Ornamental grass. Common variety is ‘Elijah blue’ |
Meadow fescue | Schedonorus pratensis (Huds.) P. Beauv. (formerly Festuca pratensis Huds.) | Similar in appearance to tall fescue. Little current use in high value turf. |
Hard fescue | Festuca brevipilla | Excellent shade tolerance, this fine fescue does not tolerate close mowing. It is often used in unmown, “native” areas of golf courses. |
Red fescue | Festuca rubra | Today, red fescue is classified into two groups: 1) Slender creeping red fescue or 2) Strong creeping red fescue. However, some seed labels may still just say, red fescue. |
Figure 1. Unmown, fine-fescue used on a golf course. These areas are often described as no-mow, native areas, or environmentally sensitive areas to the golfers. |
Figure 2. Chewings fescue. Notice the fine leaf texture (narrow leaf width) compared to tall fescue below. |
Figure 3. Tall fescue (turf-type). |
Aaron Patton, Turfgrass Extension Specialist
Senin, 17 Agustus 2015
New Lawn Recovery Guide
Lawns and the Summer 2012 Drought/Heat Crisis: Now What? | PDF
Selasa, 11 Agustus 2015
Imprelis® Update: Stop Sale, Use, or Removal Order. Q&A
Q: What action has the Office of Indiana State Chemist (OISC) recently taken concerning Imprelis®?
A: The OISC issued a stop sale, use, or removal order (SSURO) on August 1, 2011 for the herbicide Imprelis®. The OISC has reason to believe that DuPont Imprelis® Herbicide, EPA Reg. #352-793, when used as directed or in accordance with commonly recognized practice, has caused injury to non-target vegetation, except weeds to which it has been applied, and is therefore MISBRANDED. Therefore, the OISC is hereby issuing a STOP SALE, USE OR REMOVAL ORDER (SSURO) to DuPont Professional Products. This SSURO requires DuPont Professional Products to cease all sale, distribution and use of DuPont Imprelis® Herbicide, EPA Reg. #352-793, in the State of Indiana, effective immediately. This SSURO pertains to any and all quantities and sizes of DuPont Imprelis® Herbicide, EPA Reg. #352-793, within the ownership, control or custody of DuPont Professional Products wherever located. In addition, DuPont Professional Products shall not commence any movement of this product from any present location without prior written approval from the OISC. Any person violating the terms or provisions of this SSURO shall be subject to civil or criminal penalties as set forth in IC 15-16-4.
Q: What is the stance of the United States Environmental Protection Agency (EPA) concerning Imprelis®?
A: On August 11, The EPA issued a SSURO for the herbicide Imprelis®. Previously, the EPA issued a letter to DuPont on August 3, 2011 stating two concerns. First, that the EPA is considering issuing an SSURO (described above). Second, the EPA is concerned about the lack of information that is being provided by DuPont to the public concerning the efficacy of Imprelis®. The EPA “strongly encourages DuPont to reconsider” providing information related to the phytotoxicity studies related to effects on trees. More information about Imprelis, including EPA registration of the herbicide, is available at: http://www.epa.gov/pesticides/regulating/imprelis.html
Q: What action has DuPont taken to comply with the OISC?
A: DuPont is implementing a voluntary suspension of sale of Imprelis® herbicide. More information is available at http://www.imprelis-facts.com/ and at (866) 796-4783.
Q: Can I still apply Imprelis® herbicide in Indiana if I have some leftover?
A: No. The SSURO issued by OISC does not allow the continued use of existing Imprelis® herbicide.
Q: What do I do if I have leftover Imprelis® herbicide?
A: DuPont has stated that they will initiate a product return and refund program in mid-August 2011. More details about this will be shared when they become available.
Q: Where can I get more information from DuPont about Imprelis®?
A: Website (http://www.imprelis-facts.com/) and hotline ((866) 796-4783) are available.
Q: Where can I get more information from Purdue and the OISC about Imprelis®?
A: Read news alerts from the Office of Indiana State Chemist at http://www.isco.purdue.edu/, read more from the Purdue University Turf Program at http://www.agry.purdue.edu/turf/, and received updates from the Plant and Pest Diagnostic Laboratory at http://www.ppdl.purdue.edu/ppdl/.
Read past documents created on July 22, 2011
A Homeowner’s Guide to Suspected Imprelis® Herbicide Injury in the Landscape
A Turf Professional’s Guide to Suspected Imprelis® Herbicide Injury in the Landscape
Aaron Patton, Turfgrass Extension Specialist
Turf: Dead or Alive?
Step 1. In an area of suspected dead turf (brown areas), pull at the brown (dead) leaf blades.
Step 2. After pulling up some of the dead leaf blades, examine the ground closely and look for signs of new growth. All new turf growth comes from the crown of the plant (turf) and these crowns are located at or near the soil surface.
Step 3. If you find new turf emerging in these dead areas then that is good news that your turf will recover from drought and heat injury. If not, wait a few more weeks and reexamine these areas.
Step 4. If no new growth is occurring in areas you might need to reseed these spots. For lawns with bunch-type grasses such as tall fescue and perennial ryegrass, reseed dead spots larger than 3 inches in diameter. For Kentucky bluegrass lawns, reseed dead spots larger than 6 inches in diameter (about the size of your hand, or at least mine). Since Kentucky bluegrass has rhizomes (underground stems) it has a greater recuperative capacity than bunch-type grasses. The photo below shows a bare area between clumps of perennial ryegrass.
Aaron Patton, Turfgrass Extension Specialist
Certainty Turf Herbicide Label Changes
Q: What does this mean?
A: Product packaged before these changes can continue to be used according to label directions in cool season turf, but any Certainty® purchased in the future will be labeled only for use in warm-season turf like bermudagrass and zoysiagrass.
Q: Certainty® worked well on yellow nutsedge in Kentucky bluegrass, what should I use now?
A: Many herbicide options are available for sedge control in cool-season turf including bentazon (Basagran), LescoGran), halosulfuron (SedgeHammer, ProSedge, others), mesotrione (Tenacity), sulfentrazone (Dismiss), and sulfentrazone containing herbicides (Echelon, Q4 Plus, Solitare, Surge,TZONE).
Q: Certainty® was labeled for rough bluegrass control in Kentucky bluegrass and creeping bentgrass, what should I use now?
A: Velocity is the only other turf herbicide labeled for rough bluegrass control, but it is only labeled for sod and golf course use. Rough bluegrass control in residential and commercial lawns will now need to be controlled with non-selective applications of glyphosate.
Q: Certainty® was labeled for suppression and partial control of quackgrass. Are there alternatives for selective quackgrass control in cool-season turf?
A: No. Certainty® was the only herbicide labeled for selective control of quackgrass in cool-season turf (primarily Kentucky bluegrass). Quackgrass will now need to be controlled with non-selective applications of glyphosate.
Aaron Patton, Turfgrass Extension Specialist
Rabu, 05 Agustus 2015
Start Seeding Cool-Season Turf Now
The best time to seed a cool-season lawn is in the late summer to early fall. Adequate soil moisture, warm soil, and limited weed pressure allow for excellent seedling growth. Normally, we recommend seeding between August 15 and September 15 as the optimum seeding window. However, due to our cool summer and a relatively cool forecast for August, we are recommending that you can start seeding anytime now and there is no need to wait until mid-August.
It is critical to seed as early as possible within this window. Even when seeding within this window, waiting one week later to seed may mean the turf will take 2 more weeks to mature as germination and subsequent growth slows later in the fall as temperatures cool. Additionally, annual bluegrass and other winter annual weeds will be more problematic with fall seeding dates than late summer seeding dates.
Seeding early (later summer) allows the turf to maximize its establishment and rooting prior to the next summer's heat and drought.
For more information about establishment, see:
Establishing Lawn Areas From Seed (AY-3-W) | PDF
Seeding a Turf Area in the Spring (AY-20-W) | PDF
Purchasing Quality Grass Seed for Your Lawn (AY-25-W) | PDF
Establishing a Lawn from Sod (AY-28-W) | PDF
Aaron Patton, Turfgrass Extension Specialist
Watering Newly Seeded Areas
Water is necessary to initiate the germination process in seeds. As the seed imbibes water, enzymatic reactions within the seed trigger the germination process. Enzymes breakdown the energy stored inside the seed endosperm and this energy is used by the seed embryo for growth. The first visible step in the germination process is the emergence of the radicle (this is the first root)(Figure 1). Next, the coleoptile (an opaque protective sheath) emerges. The coleoptile functions to protect the emerging leaf. Lastly, the green color of the first leaf can be seen as it emerges through the coleoptile. Once the first green leaf emerges, the plant can begin to make its own energy through photosynthesis and it no longer relies on the energy that was stored in the endosperm.
Once the first irrigation or rainfall occurs after seeding, it is important to keep watering! Seedlings are very susceptible to moisture stress during the first few weeks after seeding (Figure 2). The upper 1 inch of soil should be kept moist with frequent irrigation for the first two or three weeks after planting. Germination will occur in 5 to 14 days depending on the temperature and the species planted (Figure 3).
Figure 2. Tall fescue seedlings emerging in a hydroseeded area. As new seedlings germinate they need to be watered frequently enough to avoid drying. |
After the seed germinates and seedlings develop roots into the soil, the lawn can be watered less often. Once established, the lawn should be watered deeply and infrequently only when the plant shows signs of water stress.
Aaron Patton, Turfgrass Extension Specialist