Both species are entomophilous and facultatively autogamous. Lateral stamen pollen is important for cross-pollination, central stamen pollen is utilized by both species as a pollinator reward and for delayed autogamy in C. dianthifolia, and the staminodes mimic, by means of both colour and epidermal features, large amounts of pollen to attract insects to the flowers. Pollen from all three anther morphs is capable of siring seed, although staminode pollen is inferior. The thin staminode endothecium with fewer secondary thickenings retards staminode dehiscence.

, T. 2008. Potential to double-crop plastic mulch. Can. J. Plant Sci. 88: 187Á193. Double-cropping of plastic (polyethylene) mulches has the potential to increase the cost-effectiveness while reducing the environmental impact of this technology for enhancing growth of vegetable crops. In regions with a short growing season, double-cropping of soil mulches hinges on being able to leave the plastic in the field over winter. This extended exposure to the elements may alter the physical and optical characteristics of the mulch, thereby influencing crop productivity in the second year of use. This study evaluated the physical characteristics and efficacy of black, clear and infrared transmitting (IRT) mulches over two cropping seasons in Saskatchewan. The crops planted were pepper (Capsicum annuum) and cucumber (Cucumis sativus) in the first year and tomato (Lycopersicon esculentum) in the second year. Early-season soil temperatures appeared highest under the clear mulch in the first year, but once the crop canopy was established there was little difference in soil temperature among plots having different mulches. Higher yields of both cucumber and pepper were produced in the first year by clear mulch than by black mulch or without mulch. All mulches were still physically sound at the end of the first growing season, but light transmission through the clear and IRT mulches was reduced relative to new mulch. Much of this change was due to soil and other debris on the surface of the mulches. There was little further change in the physical condition or light transmission characteristics of the mulches through the second year of use. Weed growth under clear mulch in its second year appeared to reduce soil temperatures, particularly relative to new clear mulch. Mulch type, either newly laid or year-old, had no impact on yields of marketable tomatoes. More fruit reached full red color prior to harvest in response to clear mulch than to no mulch (bare soil). Yields of marketable tomato fruit obtained on year-old mulch of all types were comparable to yields obtained with new mulch. These data suggest that double-cropping of plastic mulches can be done without loss of crop yield and provide significant savings in materials, labor and disposal costs. While clear mulch was generally the most beneficial for the production of warm season vegetable crops, it did not prevent weed growth in the second year which was problematic. 187Á193. Une culture double sur paillis de plastique (polye´thyle`ne) augmenterait la rentabilite´des cultures maraıˆche`res tout en atte´nuant l'incidence de cette technologie sur l'environnement. Dans les re´gions a`courte pe´riode ve´ge´tative, pareille pratique suppose ne´anmoins qu'on puisse laisser le plastique au champ durant l'hiver. Une exposition prolonge´e aux intempe´ries pourrait cependant modifier les proprie´te´s physiques et optiques du paillis, donc influer sur le rendement de la culture la deuxie`me anne´e. L'e´tude devait e´valuer les proprie´te´s physiques et l'efficacite´des paillis en p...

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Baseline data on the boreal jack pine associated chanterelle (Cantharellus cibarius) and pine mushrooms (Tricholoma magnivelare) in the Boreal Plain Ecozone of Saskatchewan was collected in five ecosites of productive mushroom areas. It investigated hourly weather parameters correlated with daily purchase volumes over four years; yield data over five years; varying age/ tree density/species for presence of mushrooms in over 100 stands. All plots fell within the lichen jP ecosite with an overstory entirely of jack pine. The understory was dominated by reindeer lichen, bearberry and blueberry. Plots were well- to rapidly drained, subxeric to submesic, with low nutrient regime. Both chanterelle and pine mushrooms were present in jack pine stands of < 20 years age with greatest occurrence in pure jack pine stands of 41–60 years in moderately open A-B canopy density. Weekly purchase data correlated with environmental parameters. Growing Degree Days (Base Temperature 5oC) + soil temperature (minimum 500 ± 70 GDD), + either soil moisture or precipitation (cumulative 50–100 mm) provided the highest regression value with chanterelle yield 6–13 weeks prior to first appearance. Five year total chanterelle yield from this region averaged 7100 kg/yr. Chanterelle cap diameter was a good predictor of fresh weight and proxy for yield. Pine mushroom was < 10% of chanterelle yield, averaging 1.72 kg/ha over four years based on 5 days picking. With future climate predictions of warmer and moister conditions, timing of fruiting body appearance is anticipated to advance.