I bought Katana granules last year to control a few weed species that popped up in my yard. I am pretty positive I mixed it WAY too hot. The stuff is pretty expensive so I would like to mix it according to the label because after all, dead is dead so why throw away $$ and over mix it.

What do these measurements equate to in teaspoons or fractions of teaspoons?

Is it roughly 1/2 teaspoon per gallon of water at the upper level of .068 ounces?

Attached File



And if I wanted to reduce the amount of KATANA needed by adding nitrogen to the mixture?

Would it be roughly 1/4 teaspoon per gallon at the upper level of .034 ounces? How much nitrogen is in this mixture per gallon? Thanks

Attached File

They are telling you to mix a certain mass of product into a certain volume of water.

Your brain wants the product in volume (teaspoons).  This is wrong.

You need to weigh out the amount they recommend and add it to the water.

Do you have a scale?  A reloading scale would be ideal.  They are usually calibrated in grains.  Here are the unit conversions.

0.03 ounces = 13.1 grain
0.068 ounces = 29.75 grain
1 gram = 15.4 grains
2 grams = 30.8 grains

Note the 2:1 range of recommended product, so you have wide latitude.

If you weigh out the quantity, put it in a measuring spoon to calibrate it to a volume.  From then on, you can use volume but you need a good reference point.

I usually use a fired shell and solder a handle on the side of it.
Pick one that is slightly larger and then file the length down so it holds exactly the amount you need.

If OP is interested in an accurate mix ratio, he has to be careful and weigh them all.

Using a volume in lieu of a weight is only consistent if the product density does not change.  IME, as you go from the top of the package to the bottom, the product gets crushed a bit.  The particles get smaller.  They pack more densely.  A fixed volume will hold higher and higher mass as you work to the bottom of the package.

If it has to be accurate, it has to be weighed.

Correct about my brain. And a good suggestion about the weight too. I don’t own a scale but this might be the straw that pushes me into reloading. I have been contemplating it.

With a 2:1 range on desired it does not have to be all that accurate.

When I mix weed killer,  I figure if a little bit is good, more is better.

WTH? 1 to 2 grams?

That's on a real label on something they sold to homeowners?

I'll give you the short answer. When the application rate starts at 0.5 oz per acre, you can sneeze and over mix on a gallon.

In most states, any person can purchase non-restricted pesticides, many of them still very serious pesticides labeled for commercial use etc. The big box stores may not carry them, but they're readily available.

The labels of those are not written to hold the hand of the user, they are straight forward. It is not unusual for granular products to be measured by weight.

You would be surprised what it takes for a pesticide to make the restricted use list; it takes a lot. And you would be surprised how easy it is to get a restricted-use pesticide license; I had mine around age 14.