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==Testing Without Isolating==
While using agar plates to isolate yeast colonies is the most effective way to culture wild yeast, it is not the only way. Wild yeast should be caught using DME wort as outlined in [http://bootlegbiology.com/diy/capturing-yeast/ Bootleg Biology's ''Method 1'' or ''Method 2'']. The wort's pH should be lowered to below 4.5 to avoid bacteria as much as possible. Molds may still grow in the yeast starter even with the lower pH, and should be removed by scraping them outoff of the surface of the wort. Signs of a small krausen within 1-3 days is a good sign that viable wild yeast has been collected. After another few days, the yeast will start dropping to the bottom of the collection vessel <ref name="manoaction">[http://www.homebrewtalk.com/collecting-wild-yeast.html Collecting Wild Yeast. Manoaction. Homebrewtalk. Oct 30, 2012.]</ref>.
Once the wort has fermented out (allowing 2 weeks total is a good rule of thumb), decant the beer and pitch the collected yeast into a 500ml of starter wort, again lowering the pH to below 4.5 of the starter wort. After the starter wort has been fermented, the yeast should have enough of a population to ferment out a 1 gallon batch of wort. Keep the recipe of the wort simple, and in the 1.050 gravity range. The population of the yeast should be high enough to out-compete bacteria that would be harmful, so the pH of the 1 gallon batch does not need to be lowered. After fermenting out the 1 gallon batch of beer, sample the beer to see if the wild yeast is usable or not. Wild yeasts can be highly or moderately estery, or could have undesirable flavors <ref name="manoaction"></ref>. If the flavors are undesirable, discard the yeast and try catching a different yeast.