rit is . ▁It ▁is ▁a ▁relax ing ▁and ▁sed ative ▁her b ▁that ▁is ▁used ▁to ▁indu ce ▁sleep iness , ▁and ▁to ▁calm ▁rest less ness ▁and ▁anx iety . ▁Although ▁the ▁standard ▁definition ▁of ▁la ct uc arium ▁requires ▁its ▁production ▁from ▁L act uca ▁vi ros a , ▁it ▁was ▁recognized ▁that ▁smaller ▁quantities ▁of ▁la ct uc arium ▁could ▁be ▁produced ▁in ▁a ▁similar ▁way ▁from ▁L act uca ▁s ativa ▁and ▁L act uca ▁canad ensis ▁var . ▁el ong ata , ▁and ▁even ▁that ▁lett uce - op ium ▁obtained ▁from ▁L act uca ▁ser ri ola ▁or ▁L act uca ▁qu erc ina ▁was ▁of ▁superior ▁quality . ▁ ▁Plant ▁has ▁not ▁been ▁seen ▁to ▁be ▁to xic , ▁however ▁some ▁plants ▁in ▁the ▁genus ▁contain ▁a ▁n arc otic ▁principle ▁that ▁has ▁its ▁highest ▁concentration ▁when ▁in ▁the ▁blo oming ▁period . ▁Young ▁leaves ▁and ▁st ems ▁may ▁be ▁ed ible ▁and ▁cook ed ▁and ▁e aten ▁as ▁gre ens . ▁ ▁P ests ▁Gra zing ▁by ▁de er ▁in ▁the ▁C ed ar ▁Creek ▁Natural ▁History ▁Area ▁in ▁Minnesota ▁has ▁affected ▁the ▁height ▁and ▁vertical ▁growth ▁of ▁L act uca ▁canad ensis , ▁which ▁is ▁not ▁able ▁to ▁compens ate ▁and ▁re pl en ish ▁itself ▁from ▁the ▁damage ▁resulting ▁from ▁the ▁de er ▁gra zing . ▁Eastern ▁Gold fin ch ▁occasionally ▁eat ▁se eds , ▁limit ing ▁dispers al . ▁M amm al ian ▁her b iv ores ▁brow se ▁on ▁fol