No CrossRef data available.
Published online by Cambridge University Press: 27 March 2009
1. Italian ryegrass, laid down for two years, was used to compare the value of casein and formalized casein, ammonium sulphate, calcium nitrate and urea for grassland production. Residual effects of these treatments were measured on a third-year crop of barley.
2. Single dressings of ammonium sulphate and casein were of similar value at each of three cuttings in 1956.
3. Casein treated with formalin released nitrogen much more slowly and was of little value in the early part of the growing season. Formalized casein produced significantly higher yields than casein at the later cuttings in both years, but aggregate increases from this material were much lower than those obtained from untreated casein in each season. Formalized casein increased yields considerably in the year following application.
4. Single dressings of formalized casein were also compared with ‘repeated’ dressings of ammonium sulphate, calcium nitrate and urea, in which the same total quantity of nitrogen was divided equally between cuttings. Formalized casein produced much lower yields than these ‘repeated’ dressings in the early part of the season, but was of only slightly less value at the last cut in 1956 and gave the highest yield at the final cut in 1957. Aggregate yields from repeated dressings of inorganic N fertilizers were higher than those given by single dressings of either form of casein.
5. Comparisons were also made between the yields given by ammonium sulphate, calcium nitrate and urea. Urea applied before sowing (at 0·5 cwt. N/acre) damaged germination and reduced plant establishment slightly. Under dry conditions both urea and calcium nitrate tended to give higher yields than ammonium sulphate but with adequate rain all three fertilizers gave similar yields.
To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you used this feature, you will be asked to authorise Cambridge Core to connect with your Dropbox account. Find out more about saving content to Dropbox.
To save this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you used this feature, you will be asked to authorise Cambridge Core to connect with your Google Drive account. Find out more about saving content to Google Drive.