HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Attoe, O. J. Articles by Boyle, J. R. Search for Related Content PubMed Articles by Attoe, O. J. Articles by Boyle, J. R. Agricola Articles by Attoe, O. J. Articles by Boyle, J. R.

Fertilizer Release from Packets and its Effect on Tree Growth¹

ABSTRACT

A study was made of various factors affecting the release of fertilizer from polyethylene packets. Movement of water from the soil into the packets was almost entirely in the form of vapor and was closely related to both the area and perimeter of the pinholes in the packets. Absorption of water vapor by saturated salt solutions from air maintained near 100% relative humidity was directly related to both the solubility of the salts used and to their vapor pressure lowering values. The length of time required to release the fertilizer was directly related to the size of packet and inversely related to the number of pinholes. The more soluble fertilizer constituents were released faster than the less soluble ones. The use of packets of 19-5-17 (N, P, K) fertilizer in the field generally increased by 10 to more than 100% the rates of growth in height and diameter of cottonwood (Populus deltoides Marsh.), silver maple (Acer saccharinum L.), sugar maple (Acer saccharum Marsh.), and white ash (Fraxinus americana L.).

¹ Contribution from the Department of Soil Science, University of Wisconsin, Madison. Published with the approval of the Director, Wisconsin Agr. Exp. Sta. Study was supported in part by a grant from the Wisconsin Alumni Research Foundation. Special thanks is extended to Professor D. T. Lester, Department of Forestry, Professor J. E. Kuntz, Department of Plant Pathology, University of Wisconsin, and to Mr. Rudolph D. Teschan, State Department of Natural Resources, for their counsel in setting up the field experiments.

² Professor, Research Assistant, Research Assistant (now Assistant Professor of Soils, North Dakota State University), and Assistant Professor of Soil Science, respectively, University of Wisconsin, Madison 53706.

Received for publication June 24, 1969. Accepted for publication July 7, 1969.