Anderson's Starter Fertilizer with Mesotrione (Tenacity)

Anderson's Starter Fertilizer 21-22-04 with .08% Mesotrione herbicide (trade name Tenacity) comes in a 40 lb bag.  At the recommended application rate of 4.3 lbs per 1,000 sq ft, the coverage of one bag is 9,300 sq ft.

This product is uniquely formulated to get your seed off to a fast start while preventing seedborne crabgrass seeds from germinating. Mesotrione, the active herbicide ingredient, also kills dandelions and other broadleaf weeds for up to 6 weeks after application.

Use: This fertilizer/herbicide combination is for use on Kentucky bluegrass, ryegrass, tall fescue, and fine fescue (creeping red fescue, chewings fescue, and hard fescue).  Not recommended for use on seed mixtures that contain more than 20% fine fescue, by weight. This includes the SS6000 Shady Mixture.

Do not apply to bentgrass, bermudagrass, or zoysiagrass lawns.

This product is not for use in Florida. 

Apply whenever you plant the seed, either a new lawn or overseeding an existing lawn.  Spread the fertilizer in the final step of the seeding/overseeding process.  Apply at a rate of 4.3 lbs/1000 sq ft.  Cover the entire area in two directions to insure adequate herbicide coverage to prevent crabgrass germination.

If you have fertilizer remaining, apply again in 6 weeks at 4.3 lbs /1,000 sq ft to kill new broadleaf weeds.

Do not apply more than three times in one growing season.  Save the excess fertilizer for use as a pre-emergent crabgrass application the following spring.

Spreader settings: The setting for Scott's spreaders are:

Broadcast/Rotary type:  4 1/2 (Edgeguard, Lawn Pro, Speedy Green)

Drop Type:  7 (Accugreen, Classic Drop)

Hand Held: 4.75 (Wizz Spreader)

Fertilizer:  The Starter fertilizer component of this combination product is a homogenous particle (all elements are in every particle) with a very small particle size to insure maximum dispersal across the seeded area.  It has a SGN* rating of 135 (*Size Guide Number - the diameter of the fertilizer granules expressed as millimeters X 100 ).  SGN's range from 80 (extremely fine) to 400 (extremely large).  

With a high percentage of Phosphorous (22%), this starter fertilizer helps the seedling plants put down deep roots to insure survival and faster establishment.

The nitrogen in this starter fertilizer includes 5.6% very slow release methylene urea for delayed feeding of the newly germinated turfgrass plants.

Weed Killer:  Mesotrione is a very useful herbicide because it prevents crabgrass seed germination and kills broadleaf weeds (dandelion and clover among others) on contact while allowing certain cool season turfgrass to grow in a weed-free environment.

Mesotione is in of a new class of weed killers discovered by a research scientist working for Sygenta in 1977.  He noticed that few weeds grew underneath the bottlebrush plant in his garden.  He collected a soil sample and took it to his lab where he discovered a natural herbicidal substance secreted by the bottlebrush plant called Leptospermone that suppressed other plants from growing.

Syngenta researchers mimicked this natural herbicide to create Mesotrione (trade name Tenacity), referred to as an HPPD inhibitor.  It works by preventing carotenoid production in susceptible plants.  Carotenoid protects chlorophyll (the source of green color in plants) from being degraded by sunlight.  Thus plants without carotenoid bleach white and die.

Certain cool-season turfgrasses (bluegrass, ryegrass, tall fescue, fine fescue) are able to rapidly break down Mesotrione into inactive compounds and survive, although short-term bleaching (up to 14 days) may occur, especially in fine fescues, which may thin out when exposed to Mesotrione.

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