Masana kimiyya a Tashar Bincike ta Arewa maso Yamma na Sabis na Gandun Daji na Amurka Portland, Oregon, sun ƙirƙiri abin ƙira don hasashen fashe toho. Sun yi amfani da 'yan wasa na Douglas a cikin gwaje-gwajensu amma kuma bincika bincike game da wasu nau'ikan 100, saboda haka suna tsammanin samun daidaita samfurin don wasu tsirrai da bishiyoyi.
Dukansu sanyi da yanayin zafi suna shafar lokaci, kuma haɗuwa daban-daban suna haifar da sakamako daban-daban - ba koyaushe bane mai hankali. Tare da yawan sa'o'i na yanayin sanyi, bishiyoyi suna buƙatar ƙarancin sa'o'i masu zafi don fashe. Don haka dumin bazara a baya zai fitar da toho a baya. Idan bishiyar ba ta fuskantar isasshen sanyi, ko da yake, tana buƙatar ƙarin dumi don fashe. Don haka a ƙarƙashin yanayin yanayin sauyin yanayi mafi ban mamaki, lokacin sanyi na iya haifar da fashewa daga baya.
Genes kuma suna yin birgima. Masu binciken sun yi gwaji tare da Douglas firs daga ko'ina cikin Oregon, Washington, da California. Bishiyoyi daga wurare masu sanyi ko busassun sun nuna fashe a baya. Bishiyoyin da suka gangaro daga waɗancan layukan na iya yin kyau sosai a wuraren da ƴan uwansu masu ɗumi-da-ruwa suke rayuwa yanzu.
Tawagar, karkashin jagorancin mai binciken gandun daji Connie Harrington, na fatan yin amfani da samfurin don hasashen yadda bishiyoyi za su amsa a karkashin hasashen yanayi daban-daban. Tare da wannan bayanin, manajojin ƙasa za su iya yanke shawara a ina da abin da za su shuka, kuma, idan ya cancanta, tsara dabarun ƙaura masu taimako.