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Summary Quantitative analyses of the functioning of early vascular plants have been based on quantitative aspects of their anatomy, the likely environmental conditions, and physics, chemistry and allegedly time-invariant aspects of biophysics and biochemistry. Such analyses have already addressed the mechanics of the axes of early vascular plants, the water flux/pressure gradient relations of xylem function in these plants, and of the tissue with the same conducting function in morphologically similar but not strictly vascular plants, the possible photosynthetic rate of axes based on computed stomatal conductance and the area of cells exposed to gas space inside the axis, and some aspects of water and solute flux through parenchyma tissue. The analysis in the present paper deals with aspects of the distribution of vascular tissue with especial emphasis on transport of photosynthate from sites of photosynthesis to long-distance transport conduits (phloem, or phloem-like tissue) through mesophyll (parenchym...

Summary This paper is a discussion of the significance of the recovery of remains of berries and other fruits from mediaeval and later layers at six Norwegian sites including Oslo, Bergen and Trondheim.

Summary In this paper four authors who write about plant use in the Faroe Islands before AD 1800 are dealt with. Peder Clausson (1545–1614) was a Norwegian priest who wrote the book A True Description of Norway and Surrounding Islands. He mentioned that Potentilla erecta (L.) Rausch. is used for tanning sheep leather. Simon Paulli (1603–1680). German professor in Copenhagen, says in his Flora Danica (1648) that people in the Faroes used roots of Filicales to remove stones in the kidney and bladder. Lucas Debes (1623–1675), a Danish priest who lived in the Faroes, wrote the book A Description of the Faroe Islands and their Inhabitants. He mentions that people cultivated Angelica archangelica L., which they called kvan, and Rhodiola rosea L. gives good rose-water. Jens Christian Svabo (1746–1824), a Faroese student, wrote a voluminous report on a journey to the Faroes (1781–82) which he made for the Danish government. He gives many examples of medicinal plants and has a special chapter on plant dyeing of wool.

Summary Botanical exploration in Ireland before 1800 was conducted mainly by individuals, e.g. Richard Heaton (c. 1640), William Sherard(c. 1692), CalebThrelkeld(c. 1726). There was one attempt in the mid-1700s by the Physico-Historical Society to organize a concerted programme of botanical investigation. This paper concentrates on three separate recorders of the Irish flora and their extant manuscripts, Don Philip O'Sullivan Beare (c. 1625), John Rutty (c. 1740) and Patrick Browne (c. 1780). A manuscript account of the Irish flora survives from the first quarter of the seventeenth century. Philip O'Sullivan Beare wrote Zoiloinastix about 1623, as a response to the disparaging writings of such authors as Giraldus Cambrensis. O'Sullivan Beare clearly had first-hand knowledge of some gardens and forests, and seems to have been well-versed in botany. The Physico-Historical Society of Ireland promoted natural history exploration. Dr John Rutty was the person who apparently co-ordinated the programme. Isaac Bu...

Summary Herbicide activity depends upon the inherent ability of the active ingredient (AI) to interact with the target enzyme(s) and the efficiency of its delivery at the target site(s). In this paper consideration is given to the factors which influence effective target site delivery and activity of foliage and soil-applied compounds. In the case of foliage- applied herbicides, the efficiency of retention and cuticle penetration is influenced by the stage and habit of growth of the plant, leaf age and surface characteristics, the molecular and formulation features of the AI, and the environmental conditions before, during, or after spraying. These factors may influence the efficiency of uptake, translocation and metabolism of AI en route to the target sites. The action of soil-applied compounds is influenced by the physico-chemical properties of the AI, its adsorption/desorption on the clay-humus colloidal complex, and the absorption, transport and metabolism en route to the target sites. In particular t...

Summary A detailed programme, consisting of fieldwork, herbaria and literature searches, has been carried out to prepare a seaweed flora for the county of Berwickshire in south-east Scotland. This paper describes the coastline of that county and summarises the history of marine algal survey work in the area.

Summary Ground dominated by Cladonia lichens of the sub-genus Cladina was found locally on pinewood floors on sandy or gravelly soils in north-eastern Scotland. Most sites are under mature or old planted Scots pine, Pinus sylvestris, but some in younger plantations and a few in native pinewood. Nearly all are in areas of fairly dry climate, and all are in open situations with exposure to light and wind. The vegetation, prior to 1990 not a well recognized feature of Scottish pinewoods, is distinguished in this paper as a separate community, the Cladonia ciliata — Pinus sylvestris Community. It is part of the class Vaccinio-Piceetea and resembles the lichen-rich coniferous forests in the circumpolar boreal zone, but in Scotland occurs at the extreme climatic limit of this type of vegetation. Many stands are vulnerable to trampling and land-use change, and some have little protection against such environmental vicissitudes.