Page 105 [105]
§ Seasonal aspects and plant phenology | 103
§ SEASONAL ASPECTS AND PLANT PHENOLOGY
It seems useful to attach the linkages of animal communities to plant
phenological stages. This is desirable because the apparent populations of
the catenae organised around corrumpents adapted to pterophytes often
appear together for a short time; at least some populations are apparent for
a short time only. After this, the corrumpents may enter a long diapause; the
obstants, if they need intermediary hosts, move to another zoocoenosis.
The corrumpents, especially the monophagous ones, and among them the
highly-specialised ones (such as spermophages), have adapted to their host
plants very closely. The parasites of the Neoglocianus (Ceutorrhynchus)
maculaalba (macula-alba) only have two weeks after flowering to find their
hosts in the developing poppy head (Szelényi, 1935; Schroeder and Nolte,
1952). Our own studies on Rhagoletis cerasi during 1931-1943 on the same
site (Budapest, Hűvösvölgy), showed that the adults emerged precisely when
the earliest cherries started to show colour. Due to the extraordinarily warm
spring of 1934, the cherries ripened almost a full month earlier than in 1933
or 1935, but the cherry fruit fly tracked the phenology of its host plant.
Contarinia medicaginis or C. lentis cannot provide any care of its progeny
before the flowering of the alfalfa or lentils, respectively. Coincidence
(Thalenhorst, 1951) is therefore essential for the population to remain part
of the zoocoenosis. The seasonal aspect of the zoocoenosis, by necessity,
coincides with plant phenological stages.
The aspects can be delimited by the following plant phenological stages
(not ignoring that these are not sharply differentiated): in the case of herbs,
we distinguish; 1) seedling (until the formation of real leaves); 2) stem
development; 3) flowering; 4) seed fertilisation, and; 5) seed maturation. On
trees, or perennial plants, we can distinguish five phenological stages: 1) bud¬
break or sprouting; 2) flowering; 3) seed fertilisation; 4) seed maturation,
and; 5) leaf fall. For the latter grouping, winter brings a 6" stage, while for
the overwintering annuals (oilseed rape, winter cereals) this aspect is identical
with the seedling stage. After harvest, herbs produce a fallow aspect, unless
human activity prevents this, but this is a separate aspect only from the point
of view of the phytocoenosis - but not for the animals living there. In this
zoocoenosis, for example, on wheat fallow the Cephitena pygmaei is represented
by the imago aspect of Norbanus scabriusculus, while the contemporary
aspect of the Chloropiditena pumilionis catena is represented by the adults
of C. pumilionis - Coelinius niger.
These aspects are easy to distinguish in crops, but attaching a zoocoenological
aspect to a plant phenological stage is much more complicated in other biotopes.
Our knowledge here is rather uncoordinated, and the way of naming these
species spectra (prevernal, vernal, aestival, autumnal, hyemalis, Shakleford,
1929) merely indicates the seasonal changes of the animal assemblage, and is
not identical with the above-detailed zoocoenological aspect.