Document Library: Research Briefs

An index to our poplar and willow documentation

How poplar trees influence water flow on slopes - Research Brief 19

Water flow on pastoral slopes following rainfall transfers sediment and contributes to slope erosion. Pasture cover reduces flow rate allowing more time for water absorption. Trees also influence water flow in ways that complement and enhance the effect of pasture.

Topics: Erosion Control; Farms; Poplar Information; Trees for the Farm;

Document Type: Research Briefs;

Performance of plantation poplar on the Rakaia River in Mid-Canterbury - Research Brief 18

This research brief reports on the performance of poplar clones in a trial established in 1990 by Environment Canterbury on the banks of the Rakaia River. The trial was to compare the performance of five New Zealand-bred poplar clones, with the ‘Veronese’ (Populus deltoides × P. nigra) poplar clone.

Topics: Poplar Information; Trees for the Farm; Timber;

Document Type: Research Briefs;

Do I pollard my poplars? - Research Brief 17

What is pollarding? Pollarding is reducing a tree to a stump by removing all branches. For poplars on farms the stump is left at 2 m height so animals cannot eat off the new shoots.

Topics: Cultivation; Poplar Information; Trees for the Farm;

Document Type: Research Briefs;

Effect of fertilization on growth of poplars established from poles on farmland - Research Brief 16

A single deposit of fertiliser, either N (80g urea), P (180g superphosphate) or both was supplied at 30 cm upslope of the pole and at 15 cm depth to ‘Veronese’ poplar trees on sloping pastoral land two months after the trees were planted as poles.

Topics: Cultivation; Nutrition and Fertiliser; Poplar Information; Trees for the Farm;

Document Type: Research Briefs;

Pollarding wide-spaced poplar trees on pastoral hillslopes alters root development - Research Brief 15

Water flow on pastoral slopes following rainfall transfers sediment and contributes to slope erosion. Pasture cover reduces flow rate allowing more time for water absorption. Trees also influence water flow in ways that complement and enhance the effect of pasture.

Topics: Erosion Control; Farms; Poplar Information; Trees for the Farm;

Document Type: Research Briefs;

Root development in poplar and willow clones (a pot study) - Research Brief 05

A range of willow (Salix) and poplar (Populus) clones were used in the study. This information is important for river engineers, land managers and landowners seeking to match planting material to situation.

Topics: Erosion Control; Rivers; Root Systems; Poplar Information; Willow Information;

Document Type: Research Briefs;

Influence of tree shading by Populus ×euramericana ‘Veronese’ - Research Brief 02

We measured and modelled pasture production over a 10-month period under poplar trees aged either 11 or 22 years (TP) and in open pasture (OP), to determine the effect of spaced conservation trees on pasture production.

Topics: Fodder; Cultivation; Poplar Information; Trees for the Farm;

Document Type: Research Briefs;

Wood production of ’Kawa’ poplar in an agroforestry trial - Research Brief 14

Poplar is widely planted internationally as a forestry and agroforestry species. The poplar cultivar ‘Kawa’ has been planted in Northland as an agroforestry tree. ‘Kawa’ has a higher wood density than most other poplar cultivars, with a straight stem.

Topics: Poplar Information; Trees for the Farm; Timber;

Document Type: Research Briefs;

Effect of slope position on poplar growth - Research Brief 13

Trunk diameter data from two wide spaced poplar trials planted in rows, with within row spacing of 10 m, at 20 m apart up a slope are used to provide insights into how slope position affects poplar growth.

Topics: Erosion Control; Root Systems; Cultivation; Poplar Information; Trees for the Farm;

Document Type: Research Briefs;

Influence of soil type on poplar root development - Research Brief 12

Poplar (Populus deltoides × nigra) Trees were grown from 3 m-long poles on pastoral hill slopes in three different soil types, pumice, sandy loam and clay loam, differing in their bulk density.

Topics: Erosion Control; Root Systems; Cultivation; Poplar Information;

Document Type: Research Briefs;

Willows at work in the catchment - Research Brief 11

Natural water catchments extend from mountains to sea, collecting water on the way. The erosive power of flowing water increases during periods of high water runoff, e.g. rainstorms. The heavier the rainfall the greater the water volumes and velocity the greater the erosive forces.

Topics: Erosion Control; Farms; Rivers; Willow Information;

Document Type: Research Briefs;

Willows, poplars and fodder - Research Brief 10

Poplar and willow provide fodder of sufficient quality and quantity to warrant using then as supplements for feeding to livestock during summer droughts. In addition to the feed quality, the tannins and phenolic glucosides present in the leaves provide pharmaceuticals benefits to stock.

Topics: Fodder; Poplar Information; Trees for the Farm; Willow Information;

Document Type: Research Briefs;

Milling poplar on the farm for fencing and yards construction - Research Brief 09

Farm milled poplar provides valuable wood products for both on-farm and off-farm use e.g. treated posts, battens and timber. On-farm, the timber was used for railings and gates in both cattle and sheep yards.

Topics: Poplar Information; Trees for the Farm; Timber; Farm milling & uses;

Document Type: Research Briefs;

Effect of giant willow aphid on growth of young willows - Research Brief 08

Two wide-spaced trials were planted on each of two farms in Tararua District to evaluate the effect of sap-sucking Tuberolachnus salignus, giant willow aphid (GWA), on ‘Tangoio’ tree willow growth

Topics: Pests; Giant Willow Aphid Tuberolachnus salignus ; Willow Information;

Document Type: Research Briefs;

Poplar trees and soil properties - Research Brief - 07

This study investigated the effects of poplar tree spacing on soil properties (infiltration rate, bulk density, soil moisture content and soil organic matter content) in two Nelder tree plots, with different soil types.

Topics: Cultivation; Poplar Information; Trees for the Farm;

Document Type: Research Briefs;

Willows affect pastoral soil properties - Research Brief 06

Willow trees planted for soil conservation confer beneficial effects on the soil through canopy litter, roots and shade.

Topics: Erosion Control; Farms; Trees for the Farm; Willow Information;

Document Type: Research Briefs;

Climate change and growth of Poplar and Willow trees - Research Brief 04

We evaluated the response of Populus and Salix trees to elevated carbon dioxide (CO2) and temperature, and the interaction of these factors with drought, in a controlled environment.

Topics: Poplar Information; Trees for the Farm; Willow Information;

Document Type: Research Briefs;

Killing old Poplar trees using chemicals - Research Brief 03

Large or old poplar trees considered a safety risk can be poisoned, killed and left standing, using an appropriate herbicide applied to the conducting tissue in the trunk.

Topics: Poplar Information;

Document Type: Research Briefs;

Poplars and Willows as soil conservation trees in New Zealand - Research Brief 01

This study investigated farmers’ perspectives and experiences of poplar and willow trees planted on their farms for erosion reduction.

Topics: Erosion Control; Poplar Information; Trees for the Farm; Willow Information;

Document Type: Research Briefs;