▁and ▁- 2 . 4 5 ▁M Pa , ▁respectively , ▁at ▁the ▁end ▁of ▁the ▁growing ▁season , ▁which ▁coinc ided ▁with ▁the ▁steady ▁decl ine ▁in ▁site ▁temper atures ▁and ▁a ▁c ess ation ▁of ▁height ▁growth . ▁In ▁general , ▁seed lings ▁and ▁em bl ings ▁had ▁similar ▁ ψ s at ▁and ▁ ψ tip ▁values ▁through ▁the ▁growing ▁season , ▁and ▁also ▁had ▁similar ▁sh ifts ▁in ▁season al ▁patterns ▁of ▁maximum ▁mod ulus ▁of ▁el astic ity , ▁sym pal st ic ▁fraction , ▁and ▁relative ▁water ▁content ▁at ▁t urg or ▁loss ▁point . ▁ ▁G ross nick le ▁and ▁Major ▁( 1 9 9 2 ) ▁found ▁that ▁year - old ▁and ▁current - year ▁need les ▁of ▁both ▁seed lings ▁and ▁em bl ings ▁had ▁a ▁similar ▁decl ine ▁in ▁need le ▁conduct ance ▁with ▁increasing ▁v ap our ▁pressure ▁def ic it . ▁Response ▁surface ▁models ▁of ▁current - year ▁need les ▁net ▁photos yn thesis ▁( P n ) ▁response ▁to ▁v ap our ▁pressure ▁def ic it ▁( VP D ) ▁and ▁photos yn th et ically ▁active ▁radiation ▁( PAR ) ▁showed ▁that ▁em bl ings ▁had ▁ 1 5 % ▁greater ▁P n ▁at ▁V PD ▁of ▁less ▁than ▁ 3 . 0 ▁k Pa ▁and ▁P AR ▁greater ▁than ▁ 1 0 0 0 ▁ μ m ol ▁m − 2 s − 1 . ▁Year - old ▁and ▁current - year ▁need les ▁of ▁seed lings ▁and