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<br />c....j"'l <br />co <br />.:.;.; <br />""'" <br /> <br />,..h, <br />,.. <br /> <br />All o...cha...d sites had high appl ication efficiency which va...ied f...om 59 <br />to 74% <Tab I e 2). The o...cha...ds had the highest app I i cat i on <br />efficiency, 68%, compa...ed to all othe... c...ops g...own in the Valley. <br />Wate... appl ication amount was also the lowest compa...ed to othe... sites <br /><Tab I e 2). Compa... i son of six yea...s of o...cha...d data <Tab I e 8) show <br />that f...om 1985 to 1990, the amount of wate... appl iGation, ...unoff, and <br />deep pe...colation has been dec...easing. Appl ication efficiency <br />inc...eased du...ing this pe...iod. <br /> <br />G...apes: Only one site with about 3 ac...es (1.4 acres wetted a...ea) was <br />monito...ed in 1990. Twenty i......igation events we...e ...eco...ded. <br /> <br />The i......igation volume and deep pe...colation data in Table 2 fo... g...apes <br />have been based on wetted ac...eage. Due to plant spacing and <br />mic...osp...ay patte...n, only about 50% of the total feld ac...eage gets <br />wetted du...ing i......igation. The site is i......igated ..ith a mic...osp...ay <br />i...... i gat i on system wh i ch gene...a II y has about 75 to 80% app I i cat ion <br />efficiency. In 1989 and 1990, the maximum potential efficiency was <br />assumed to be 90% with 10% evapo...ative losses. Prio... to 1989, <br />potential efficiency was estimated to be 80% with 20% evapo...ative <br />losses. When all data is ...ep...ocessed fo... 1985 th,"ough 1989 with the <br />updated wate... budget p...og...am the disc...epancies wi I I be co......ected. <br /> <br />Compa...ison of g...ape data f...om 1985 th...ough 1990 show that deep <br />pe...colation was ...educed f...om 10.7 inches in 1985 and 1986 to 2.3 <br />inches in 1987. In 1988, the deep pe...colation losses inc...eased to 4.3 <br />inches and then dec...eased to 2.3 inches in 1989 and inc...eased again in <br />1990 to 5.6 inches <Table 8). The deep pe...colation losses in 1990 was <br />30% highe... than the acceptable deep pe...colation requi...ed fo... salt <br />leaching <Table 6). <br /> <br />In 1990, al I of the deep pe...colation losses occu...red by the end of the <br />thi...d i......igation. Du...ing the ...est of the season the c...op wate... need <br />was neve... met. Because of no deep pe...colation afte... the thi...d <br />i......igation, the efficiency fo... each i......igation event came out ve...y <br />high and the ove...a II eff i c i ency of 73% is not a tr"ue i nd i cat i on of <br />good wate... management p...actices. P...oduction was ve...y low in 1990. <br />I......igation efficiency is 73% fo... site 17. However", This site was not <br />managed as well as it should. <br /> <br />Soi I sal inity testing in 1987 showed that the...e was a sl ight inc...ease <br />in salt build-up at site 17. The mino... inc...ease in deep pe...colation <br />in 1988 did not show any dec...ease in sal inity at site 17. The...e was a <br />dec...ease in deep pe...colation and soi I sal inity at site 17 in 1989. <br />Howeve..., in 1990 soi I sal inity inc...eased even though the...e was an <br />inc...ease In deep pe...colation at the site. Refe... to part 2. <br /> <br />Beans: Two sites, 27 and 48 we...e establ ished in l~l90. A total of 12 <br />i......igation events on 22 ac...es we...e monito...ed. Both sites have su...face <br />i......igation systems. <br /> <br />27 <br />