Not so clear - if using John Deere 2-Cycle oil 50:1 - all others 32:1. Below pasted from JD website
For 2-cycle engines, most commonly used on string trimmers, chain saws and blowers, you must mix the unleaded fuel with a high-quality 2-cycle engine oil.
To ensure the proper fuel mix ratio, use John Deere Premium Exact Mix 2-Cycle engine oil. When this oil is properly mixed it can be run in any 2-cycle unit no matter what the mix ratio is.
Use 2.6 ounces of Exact Mix oil; thoroughly mix the entire contents with 1 gallon (approximately 4 liters) of fresh, unleaded gasoline. This is a 50:1 fuel to oil mix. Exact Mix engine oil provides complete lubrication protection for any 2-cycle engine. If using other name brand, quality two cycle engine oil, mix 4.0 ounces of oil with one gallon of fresh, unleaded gasoline. This is a 32:1 fuel to oil mixture.
Additionally, Exact Mix oil contains an antioxidant fuel stabilizer. Under average conditions, fuel will stay fresh up to 30 days.
We do not recommend the use of Ethanol gasoline in any of our hand held products.
Do not use motor oil or marine two cycle oil in these engines. These oils do not meet the same specifications and internal engine damage may occur.