However, the data of literature sources about the depth of covering of rhizomes is
quite contradictory. Most researchers recommend to cover rhizomes at a depth of 8 ...
10 cm [8, 9, 10]. In the UK, they are covering rhizomes at a depth of 5 ... 10 cm in
disposable cups, which provides very good sprouts (95%), although they increase the
time period of planting [11, 12, 13].
Small rhizomes (lesser than 10 cm), planted very deep, cannot always overcome
the distance needed to sprout new shoots on the soil's surface, and it is believed that
the depth of 4 ... 6 cm is normal [14, 15, 16], although a number of other scientists
suggest a greater depth of covering – 12 ... 15 cm [17, 18] because the covering depth
of wrapping is about to control frost and winter hardiness. The deep rhizomes' covering
contributes to a somewhat deeper placement of tillering node, and the deeper the
tillering node is, the less likely it is to freeze. It is known that in the upper layers of the
soil, the temperature in winter increases by about 3 °C per centimeter of depth.
However, too deep covering does not contribute to overwintering, the sprouts appear
weakened and behind time.
Consequently, the cultivation of Giant Miscanthus is a promising direction in the
development of bioenergetics. But the introduction of this crop into the production
requires a more detailed study of morphological and biological characteristics of the
plant, depending on time of planting and the depth of rhizomes' covering.
Research results. Duration of interstage and vegetative periods of
Miscanthus, depending on the time of planting and the depth of rhizomes'
covering. The plant organism absorbs water and nutrients, accumulates energy, carries
out numerous metabolic reactions, and as a result, it grows and develops. The processes
of growth and development are closely interconnected and depend on separate
techniques, in our case, on observations over the time of planting and the depth of
covering of rhizomes. A rapid growth can be accompanied by a slow growth or vice
versa - a rapid development by a slow growth. The criterion for development rate is the
transition of plants from one stage of development to another. Plants' growth and
development processes are affected by numerous, both external and internal factors.
Observations over the development of plants are needed in order to make a more
precise study of their requirements to living conditions and, in this connection, choose
the time period and depths of covering, with which one can create the most favorable
conditions for the production of biomass.
The following phenological phases of development are typical for Giant
Miscanthus: sprouts, three leaves, tillering, stem elongation, emerging of panicle,
flowering, wilting of leaf and stem mass.
From the observations over the plants of Miscanthus having different time of
rhizomes' planting, the sprouts shall appear on the 25-30 days depending on the depth
of covering. Usually, one sprout grows from the rhizome, then it becomes the main
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