?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.relation=https%3A%2F%2Forgprints.org%2Fid%2Feprint%2F10066%2F&rft.title=Effects+of+cutting+frequency+on+plant+production%2C+N-uptake+and+N2+fixation+in+harvested+and+below-harvest+plant+biomass+of+grass+clover&rft.creator=Vinther%2C+F.P.&rft.subject=+Nutrient+turnover&rft.subject=+Pasture+and+forage+crops&rft.subject=Farm+nutrient+management&rft.description=Nitrogen+(N)+accumulating+in+stubble%2C+stolons+and+roots+is+an+important+component+in+N+balances+in+perennial+ryegrass-white+clover+swards%2C+and+the+effects+of+cutting+frequency+on+the+biomass+of+above-+and+below-harvest+height+were+studied+during+two+consecutive+years.+Total+dry+matter+(DM)+and+total+N+production%2C+and+N2+fixation%2C+were+measured+at+two+cutting+frequencies+imposed+in+the+summers+of+two+years+either+by+cutting+infrequently+at+monthly+intervals+to+simulate+mowing+or+by+frequent+cutting+at+weekly+intervals+to+simulate+grazing.+Total+DM+production+harvested+was+in+the+range+3000+-+7000+kg+DM+ha-1+with+lower+DM+production+associated+with+the+frequent+cutting+treatment%2C+and+it+was+significantly+affected+by+the+different+weather+conditions+in+the+two+years.+The+higher+cutting+frequency+also+reduced+the+biomass+below+harvest+height%2C+but+the+different+weather+conditions+between+years+had+less+effect+on+stubble+and%2C+in+particular%2C+root+biomass.+The+biomass+of+white+clover+roots+was+significantly+lower+than+that+of+perennial+ryegrass+roots%2C+and+remained+at+a+relatively+constant+level+(200-500+kg+DM+ha-1)+throughout+the+experiment%2C+whereas+the+biomass+of+perennial+ryegrass+roots+increased+from+2+400+kg+DM+ha-1+in+the+year+of+establishment+to+10+200+kg+DM+ha-1+in+the+infrequent+cutting+treatment+and+6+650+kg+DM+ha-1+in+the+frequent+cutting+treatment+by+the+end+of+the+experiment%2C+giving+shoot%3A+root+ratios+of+4.7+%E2%80%93+16.6+and+0.5+%E2%80%93+1.6+for+white+clover+and+perennial+ryegrass%2C+respectively.+Annual+N2+fixation+was+in+the+range+28+%E2%80%93+214+kg+N+ha-1%2C+and+the+proportion+of+N+fixed+in+stolons+and+roots+was+on+average+0.28.+However%2C+since+the+weather+conditions+affect+the+harvested+DM+production+and+the+shoot%3A+root+ratio%2C+care+must+be+taken+when+estimating+total+N2+fixation+based+on+an+assumed+or+fixed+shoot%3A+root+ratio&rft.date=2006&rft.type=Journal+paper&rft.type=NonPeerReviewed&rft.format=application%2Fpdf&rft.language=en&rft.identifier=%2Fid%2Feprint%2F10066%2F1%2F10066.pdf&rft.identifier=+++Vinther%2C+F.P.+++(2006)+Effects+of+cutting+frequency+on+plant+production%2C+N-uptake+and+N2+fixation+in+harvested+and+below-harvest+plant+biomass+of+grass+clover.+++Grass+and+Forage+Science%2C+61%2C+pp.+154-163.++++++++