Showing papers by "Forest Research Institute published in 1971"

Mycorrhiza and Litter Decomposition

Abstract: FORMATION of the mor type of forest litter, characterized by slow decomposition, has been attributed to a number of factors1–3, but the effect of mycorrhizal fungi, though postulated4,5, has not been studied experimentally. We have conducted an experiment in which root activity and thus mycorrhizal activity were reduced in small areas of an unthinned Pinus radiata stand. The following treatments (three replicates in a randomized block design) were applied to 1 × 1 m plots sited between the trees.

A Contribution towards the Revision of the Agaricales (Fungi) from New Zealand

Abstract: Summary Species of Agaricales (Fungi) described or recorded from New Zealand between 1855 and 1968 are listed, together with comments on their taxonomic position. Controversial species are illustrated and important microscopical characters briefly described. A number of new combinations are proposed.

The nutritional role of Lupinus arboreus in coastal sand dune forestry

Abstract: In the artificial plant succession used to stabilise coastal sand dunes in New Zealand,Lupinus arboreus is sown into plantedAmmophila arenaria stands primarily to provide shelter for youngPinus radiata trees. Recent observations have suggested that the lupin may play a nutritional, as well as a physical part in the stabilisation technique. Work elsewhere with otherLupinus spp. and forest crops supports this theory. An attempt is being made to evaluate the significance ofL. arboreus at Woodhill State Forest with a view to possible manipulation of nitrogen supply to the tree crop. Work described in this preliminary paper has established that the presence of undamaged lupin plants can increase nitrogen uptake inP. radiata through the influence of litter and seedling exudate. Their effect could be due to direct nitrogen transfer or to stimulation of non-symbiotic nitrogen fixation. Lupin leaf washings were shown to contain ninhydrin-positive substances but did not influence nitrogen uptake byP. radiata seedlings in this experiment.

Phytophthora cinnamomi in indigenous plant communities in New Zealand

Abstract: Summary Phytophthora cinnamomi has been isolated from roots of 25 species of plants found in four indigenous communities in three of which severe chlorosis, dieback and mortality occur. The most severely affected are dense kauri (Agathis australis) regrowth stands 80–100 years of age in the Waitakere Ranges near Auckland where both overstorey and understorey species are severely damaged. The other diseased communities are mixed scrub on eroded hill soils at Kaitenteri near Motueka and Coriaria sarmentosa scrub in Golden Downs State Forest near Nelson. The fourth community is healthy Dacrydium cupressinum forest at Harihari, South Westland. From these and other records it is obvious that P. cinnamomi is widely distributed in native communities in New Zealand. It is not possible to determine whether the fungus is indigenous or introduced. It seems clear, however, that P. cinnamomi is now playing a role in natural succession. While its selective influence is likely to be subtle and protracteprotracted in mos...

Pheromone and terpene attraction in the bark beetle Ips typographus L.

Abstract: Es wird gezeigt, dassIps typographus L. primar durch Terpene und sekundar durch Pheromon der Mannchen zu den Brutstammen gelockt wird.

Contributions to the knowledge of the Agaricales s.l. (Fungi) of New Zealand

Abstract: Summary Keys for determining genera of Agaricales (Fungi) occurring in New Zealand are presented. Five new genera are described and illustrated: Pleurella, Notholepiota, Tympanella, Crucispora, and Gigasperma.

Nitrogen supply, apical dominance and branch growth inPinus radiata

Abstract: Branch development inP. radiata seedlings and young trees is affected by the level of nitrogen supply. A marginal nitrogen deficiency reduces branch and stem diameter growth much more than it does stem height growth. On soils of low N content mature trees have better than normal form. Fertilizing young trees may have undesirable side effects such as promoting branch growth and reducing leader dominance.

Plant growth substances in pollen of Pinus radiata at different levels of germination

Abstract: Summary Growth substances in germinated and ungerminated Pinus radiata pollen were examined by extraction and bioassay. Thirteen active substances were detected: five auxins, three inhibitors, four gibberellins, and one compound with some properties characteristic of both gibberellins and cytokinins. As the pollen germinated in vitro the quantities of some of these subtsances increased, others decreased, and still others remained constant. It is probable that the substance with both gibberellin and cytokinin affinities has a role in pollen-tube growth; and it is possible that, in vivo, one of the aqueous auxins may have a role in ovule development. Possible roles for some of the other hormones are briefly discussed.

Electron-microscope preparation techniques applied to the light microscopy of the cambium and its derivatives in Pinus radiataD. Don.

Abstract: SUMMARY Epon 812 was used successfully as an embedding medium for the preparation of the secondary meristem and its derivatives in Pinus radiata for light microscopy. Specimens were fixed in glutaraldehyde followed by osmium tetroxide solution, using a schedule developed for the electron microscopy of these tissues. Sections from 2 to 5 μm thick were cut using an LKB Ultratome III and glass knives. Sections were evaluated without prior removal of the embedding medium using bright-field, phase-contrast and interference-contrast microscopy. Results for cambium were generally superior to those obtained by using the conventional fixatives for light microscopy and paraffin embedding. The advantages and disadvantages of this technique are discussed and it is concluded that the use of Epon for embedding this type of material is easier and gives better results than older established methods. It is suggested that methods of electron microscopy be considered when the preparation of a material for light microscopy has proved difficult or impossible by other means, or when particularly thin sections are required.

Silvicultural Practices Adapted to Seed Supplies for Natural Regeneration of Mountain Ash (Eucalyptus regnans) in Tasmania

Abstract: SUMMARY Virgin forests of mountain ash (Eucalyptus regnans F.Muell.) have all originated after wild fires. Similarly, natural regeneration after logging is promoted by burning in later summer to kill the undergrowth and prepare a receptive seed bed, and providing for adequate and timely seed dispersal from reserved seed trees. Seed trees should be selected for the size and vigour of their crowns, and their seed crop should be assessed after the remainder of the utilisable trees have been felled. A practical method of forecasting seed crops by telescope has been developed so that either (a) additional seeding, if shown to be required, can be carried out while the seed bed is still receptive, or (b) the regeneration burn can be timed to make use of adequate seed crops where these occur. Failures of the initial regeneration treatment cannot be recognised till the spring after the regeneration burn because a very variable and often major part of the regeneration stems from germinations in early spring. Assess...

Two new ectotroph-forming boletes from India

Abstract: Pulveroboletus shoreae sp. nov. andXerocomus bakshii sp. nov. (Boletaceae) are described as new. Observations at the type locality show that they are both connected with short roots of the ectotrophic-mycorrhizal type, theXerocomus withPinus roxburghii, thePulveroboletus withShorea robusta, Fam. Dipterocarpaceae. This latter family has not been shown to form ectotrophs with ectotrophically mycorrhizal Basidiomycetes before our present research.

Seed Production Costs for Radiata Pine Seed Orchards

Abstract: SUMMARY Predictions of quantities of seed produced at various ages, and costs of production in radiata pine seed orchards are presented. They have been drawn from the actual and forecast production of a number of radiata pine clonal seed orchards in south east Australia. Two production curves are presented to show what might be expected from a moderately good and a poorer quality site. Net discounted revenues based on the two production curves have been calculated for a range of seed values, at 6, 7 and 8 per cent compound interest, and possible rotations of IS and 20 years. Using the same calculations in reverse, seed production costs may be determined from known or estimated net discounted operational costs. A number of examples are calculated, with and without the additional costs of plus tree selection and progeny testing. The range of on-tree seed values is from $4.50 to $16.30 per lb of cleaned seed, with a median value of $8 to $10 per lb. Assuming that collection, extraction, and packaging costs a...