Trees are generally assumed to be symplastic phloem loaders. A typical feature for most wooden species is an open minor vein structure with symplastic connections between mesophyll cells and phloem cells, which allow sucrose to move cell-to-cell through the plasmodesmata into the phloem. Fraxinus excelsior (Oleaceae) also translocates raffinose family oligosaccharides in addition to sucrose. Su...

The transmission spectra of bud scales of 14 woody species and the 77 K fluorescence emission spectra of the innermost leaf primordia of closed and opened buds of 37 woody species were studied. Pigment concentrations were determined in some species. Bud scales had low transmittance between 400 and 680 nm with a local minimum around 680 nm. Transmittance increased steeply above 680 nm and was > ...

Tree seedling flooding tolerance for 22 species was assessed under controlled field condi­ tions. Initial heights under control (freely draining soil, n = 20 per species) and flooded (stand­ ing water, depth = 10 cm, n = 20 per species) conditions were measured in March 1990. Sur­ vival, height and diameter growth were determined after 120 days. Recovery from flooding effects was assessed in th...