Thanks Harold and Jerry. Helpful information on timing. Jerry, if you have time, could you clarify your comment, "Urea application on peach in New Jersey have not been observed to be effective in increasing tissue N in leaves buds and shoots. (Much research on this subject in Fruit Nutrition by Childers and others)"?
Are you saying all the N absorbed through the leaves is translocated to the roots, or that N is not absorbed through the leaves at all? I've read that a foliar N application in the fall can delay bloom in peach, but can't remember where I read it. Perhaps an article in a trade magazine. When I googled it, this is all I could find. "For example, the application of foliar nitrogen in the autumn delayed the bloom of peaches compared to untreated controls (Reeder & Bowen, 1981). " http://www.ccsenet.org/journal/index.php/jps/article/viewFile/52934/28326 Mark On 9/10/17, Jerry Frecon <je...@acnursery.com> wrote: > From Roger Duncan, Pomology Farm Advisor, UC Cooperative Extension, > Stanislaus County > "Fall can be an excellent time to apply certain nutrients if trees are > deficient. > Nitrogen. Nitrogen utilized by trees and vines for early season shoot and > fruit growth comes > from reserves stored in the roots and other woody tissues of the plant. This > is why it is > important to enter into dormancy with adequate nitrogen reserves. UC > Extension pomologist > Scott Johnson has shown that a low biuret urea foliar spray just prior to > natural leaf senescence > is an excellent method of supplying nitrogen to peach trees. At least 80% of > the nitrogen is > absorbed into the leaf within 24 hours. The nitrogen is then readily > translocated out of the leaf > and into long-term storage. Trees low in nitrogen because of nematodes, a > high water table or > other root problems should certainly benefit from this spray. This is also > an excellent way to > provide nitrogen without risk of ground water contamination. > Each spray supplies about 50 pounds of actual N per acre. That means if a > granular > formulation of low biuret urea is used (which is almost 50% N), you need to > apply about 100 > pounds of product per acre. If a second application is necessary, it should > be applied at least > two weeks after the first application. Within a few days, you should start > to see some burn > along leaf margins and at the tips. Defoliation will probably progress a > little more quickly than > normal." > > Urea application on peach in New Jersey have not been observed to be > effective in increasing tissue N in leaves buds and shoots. (Much research > on this subject in Fruit Nutrition by Childers and others) If N tissue > levels were increased as they are with N soil applications then N deficient > peach trees may be healthier and more winter hardy, I am not aware of any > research demonstrating a delay in bloom with urea foliar applications. > > Jerome L "Jerry" Frecon > Professor Emeritus, Rutgers University > And Horticultural Consultant for > www:jerseypeaches.com > www.acnursery.com > > -----Original Message----- > From: apple-crop [mailto:apple-crop-boun...@virtualorchard.com] On Behalf Of > Mark Angermayer > Sent: Sunday, September 10, 2017 1:46 PM > To: email@example.com > Subject: [Apple-Crop] Timing of foliar nitrogen in peach > > I've read foliar urea in fall can increase hardiness and delay bloom on > peach. > > Can anyone tell me the optimum time to apply foliar urea (100 lbs./ac > - i.e. 50 lbs. actual N) on peach? I'd like to use regular soil urea (vs. > the low biuret) because of cost, but understand soil urea will burn the > foliage. > > I don't want to apply it too early so as to minimize photosynthesis from > premature leaf drop, but don't want to apply it too late so the leaves won't > absorb the N. > > U of C says to apply it in Sept. or Oct. (not Nov.) but the climate out > there is quite a bit different than here. > > Anyone have a good general guideline to go by (i.e. just before leaf drop, > two weeks before leaf drop, etc.)? > > http://ucanr.edu/sites/fruitreport/Nutrition_-_Fertilization/Individual_Nutrients/Nitrogen/Foliar_Urea/ > > http://ucanr.edu/sites/fruitreport/files/162635.pdf > > Thanks, > Mark Angermayer > Tubby Fruits Peach Orchard > KS/MO > _______________________________________________ > apple-crop mailing list > firstname.lastname@example.org > http://virtualorchard.com/mailman/listinfo/apple-crop > _______________________________________________ > apple-crop mailing list > email@example.com > http://virtualorchard.com/mailman/listinfo/apple-crop > _______________________________________________ apple-crop mailing list firstname.lastname@example.org http://virtualorchard.com/mailman/listinfo/apple-crop