Izazinzulu kwi ISikhululo soPhando seNkonzo yamaHlathi sase-US Pacific Northwest IPortland, eOregon, iphuhlise imodeli yokuqikelela ukugqabhuka kwehlumela. Basebenzise iDouglas firs kuvavanyo lwabo kodwa baphinde bavavanya uphando malunga nezinye iintlobo ze-100, ngoko ke balindele ukukwazi ukulungelelanisa imodeli yezinye izityalo nemithi.
Zombini ubushushu obubandayo kunye nobushushu buchaphazela ixesha, kwaye indibaniselwano eyahlukileyo ivelisa iziphumo ezahlukeneyo - ayisoloko inembile. Ngeeyure ezininzi zobushushu obubandayo, imithi idinga iiyure ezimbalwa ezifudumeleyo ukuze igqabhuke. Ke ukufudumala kwangaphambili kwentwasahlobo kuya kuqhuba i-bud iqhume ngaphambili. Ukuba umthi awuvezwanga kubanda ngokwaneleyo, nangona kunjalo, ufuna ubushushu obungakumbi ukuze ugqabhuke. Ngoko ke phantsi kwezona meko zibalulekileyo zokutshintsha kwemozulu, ubusika obufudumeleyo bunokuthetha ukugqabhuka kwentyatyambo kamva.
Imfuza idlala umqulu, nayo. Abaphandi bavavanya iDouglas firs ukusuka ngaphaya kweOregon, Washington, naseCalifornia. Imithi evela kwindawo ebandayo okanye eyomileyo ibonise ukugqabhuka kwangaphambili. Imithi ephuma kuloo migca inokuhamba ngcono kwiindawo apho abazala babo abafudumalayo nabanobumanzi bahlala ngoku.
Iqela, elikhokelwa yihlathi lophando uConnie Harrington, linethemba lokusebenzisa imodeli ukuqikelela ukuba imithi iya kuphendula njani phantsi kweengqikelelo ezahlukeneyo zemozulu. Ngolo lwazi, abaphathi bomhlaba banokugqiba ukuba batyale phi kwaye batyale ntoni, kwaye, ukuba kukho imfuneko, bacwangcise izicwangciso zoncedo lokufuduka.