InSitu 95: Paper No 11
            "Methods of selection work to improve the resistance factor of
                     protective forests in Russia arid zone"
                                 by:   H.Mattis

       Index of Contents:

 

 Introduction
        
        The principal targets for protective afforestation in Russia
        are regions with severe soil and climatic conditions, that is there is
        a lack of moisture, frequently recurring droughts, dry winds, freezing
        winters, salinity and alkalinity of the soils, and a susceptibility of
        the tree species to diseases and pests. All these factors create
        difficulties for the establishment of effective and resistant
        shelterbelts.
                At the same time shelterbelts exert an extensive and positive
        effect on agriculture in arid zone of the contry. Shelterbelts
        contribute to increased yield of agricultural crops, protect the soil
        from water erosion and wind erosion, and so on.
                This paper summarizes the experience of the All-Russia
        Scientific Research Institute of Agroforestry Amelioration (VNIALMI)
        in breeding tree species that are utilized in Russia.
        Breeding of Introduced Species

        VNIALMI carries out the selection of the most resistant species
        in arboreta located in three regions. These arboreta, located in the
        arid zone, differ in regard to the tree growing conditions. The
        arboretum in the Central Povolzh'e (Samara city) was established in
        1950 on ordinary loamy chernozems, has a mean annual temprature of 3.7
        C (maximum +40 C, minimum -45 C), a relative humidity of 46% and a
        total precipitation of 395mm. The arboreta in the Lower Povolzh'e
        (Volgograd and Kamyshin) were established in 1910 and 1962 on chestnut
        soils, have a mean temperature of 5.4 to 7.6 C (maximum 41 to 43 C,
        minimum -35 to -39 C), a relative humidity of 40 to 41% and a total
        precipitation of 350 to 386mm. The arboretum in Western Siberia
        (Kulunda, Altai Territory) was established in 1977 on chestnut
        light-loamy soils, with a mean annual temperature of 1.9 C (maxium
        +41 C, minimum -50 C), a relative humidity of the air of 50% and a
        total precipitation of 270mm.
        
        Of 281 species, hybrids and cultivars tested at Central
        Povolzh'e, the most promising for afforestation in the chernozem
	steppe were found to be: Betula pendula Roth, Quercus robur L, Larix sibirica
        Ledeb, Pinus sylvestris L, Populus pyromidalis X P. chinensis,
        P. pyramidalis X P. nigra, and P. balsamifera X P. berolinensis.
                
	Of the 734 species, hybrids and forms that were tested in the
        Lower Povolzh'e arboreta, the most promising for field shelterbelts
        were: Robinia pseudoacacia L, Ulmus pumila L, Quercus robur L, Pyrus
        communis L, Gledistia triancanthos L, and Fraxinus lanceolata Borkh;
        for anti-erosion plantations: Crataegus species, Caragana arborescens
        Lam, Amorpha fruticosa L, Cotinus coggygira Scop and Ribes aureum
        Pursh; while for pasture-protecting shelterbelts: Crataegus monogyna
        Jacq, Colligonum sp., Halloxylon aphyllum (Minw.) Iijm, and Tamarix
	sp.
                Of 120 species, hybrids and forms tested in Western Siberia,
        the most promising have been acknowledged as: Betula pendula Roth,
        Pinus sylvestris L. and Ulmus laevis Pall. When the ground water is
        available to the roots, the greatest growth and a high winter
	hardiness were shown by the poplar hybrids: Populus pyramidalis X P.
	berolinensis and P. nigra X P. berolinensis X P. canadensis.
        Plus Tree Selection
        The principal features, used for the superior populations,
        species and cultivars are drought, salt and frost resistance, as well
        as resistance to pest and diseases.
                Since in most regions there are no native populations of woody
        plants, the selection of the plus individuals or populations for
        protective afforestation is carried out in estabished old shelterbelt
        plantings, which during the process of their growth have undergone a
        systematic exposure to extreme conditions and, survived.
                Such a combination of unfavourable weather conditions has
        occurred during the past 20 years over an extensive area of the
        European part of Russia. The severe snowless winters of 1968/69 and
        1971/72 and the severe droughts in 1972 and 1975 resulted in massive
        dieback of shelterbelts in the South-East of the European territory of
        the country. After such extereme years almost all of the shelterbelts
        were candidates for the selection of superior trees and shrubs. The
        serviving individuals and entire plantations provide a valuable gene
        pool for producing improved, hardy shelterbelt plantations.
                In addition, the native forests and "kolkas" which grow in
        depressed sectors of the topography are used in the improvement
        program. Their range occasionally extends into the regions of
        shelterbelt planting. These populations of tree species are also of
        considerable importance for breeding and seed peoduction purpeses. It
        is the sections of the natural forests on upland, dry sites that are
        targeted for the selection of parental (plus) populations and
        individual trees, even though in their growth and condition they are
        inferior to the sections of the stand growing on the bottom or on the
        lower part of the slope of the ravines.
                Finally, individual long-lived trees that have survived under
        severe conditions and which are growing in old forest belts, tree
        plantations, park and farms, should provide the basis for establishing
        seed plantations for protective afforestation.
                The plus trees that have been selected are marked with a ring
        and numbered, and registration plates are placed on them. Vegetatively
        and seed propagated test planting of these plus trees are established.
        After prolonged evaluation of their perfomance, conclusions are made
        concerning the quality of the selected gene pool. The best clones and
        populations are planted in seed orchards. The new progeny is more
        resistant and long-lived under severe growing conditions.On the basis
        of this method, VNIALMI has selected individual specimens of oak, elm,
        locust, pine and other trees, which are distinguished by a high
        resistance to drought, salinity, frost and diseases in the dry steppe
        and in semi-desert.
        Breeding of Hybrids
                Further improvement in the ameliorative effect and longevity
	of shelterbelts under steppe conditions may be achieved by the
        introduction of hybrids of tree species. Work on hybridization in the
        field was initiated at the VNIALMI research station at Kamyshin in
	1939 by A.V.Al'benski. At the present time hybrids of oak, pine, elm, ash
        and poplar have been developed that are especially promising for
        shelterbelt planting. As has been shown by studies conducted over many
        years, the majority of these species have superior growth and form.
        In the hybridization of oaks the pedunculate oak (Quercus
	robur L) was taken as the maternal tree, while the red oak (Q. rubra L) was
        taken as the pollinator. In the hybrids, the growth in height during
        the initial years was 1.5 times as great as in the parental species.
        At an age of 18 years the difference in height was 23.7 to 77.6%,
        while the difference in diameter ranged from 10.2 to 100.0%. On the
        basis of the intensity of transpiration, the accumulation of dry
	matter and the water-retaining capacity of the leaves, the hybrids occupy an
        intermediate position in comparison with both of the control species.
        Their heat tolerance is higher than that in the pedunculate and red
        oaks. In addition, the hybrids obtained have shown improved resistance
        to infection by vascular mycisis (a widely distributed disease of
	oak).
                For the hybridization of pines, the Scots pine (Pinus
        sylvestris L) and Crimean pine (P. Pallasiana Lamb.) were used. Both
        species were used as maternal trees and as pollinators. They are
        widely utilised for the afforestation of light soils, and in this case
        the Scots pine grows more rapidly, while the Crimean pine is more
        salt-tolerant. the average height of a 20 year old hybrid is 18 to 20%
        higher than that of either of the maternal species. The hybrid also
        surpasses the maternal species by 18% D.B.H. On the basis of the
        intensity of transpiration the hybrids occupied an intermediate
        position between the parental species.
                In the hybridization of elms, the Siberian elm (Ulmus pumila
	L)which was introduced from Central Asia, was used as the maternal tree.
        This species is distinguished by its rapid growth, drought and salt
        resistance, but is not fully frost hardy. The progeny obtained from
        the pollination of this species with the pollen of the smooth-leaves elm
        (U. carpinifolia Rupp) and the "common" elm (U. laevis Pall.) markedly
        exceeded the parental species in their growth. The heterosis in growth
        was retained also in the third seed generation. The drought resistance
        in the hybrids obtained was also higher than in the parental specias.
                Of special importance to field shelterbelt afforestation is
	the poplar (Populus sp.), which is distinguished by its rapid growth and
        great height. The hybrids with a pyramidal form allow one to allocate
        a minimal area to the shelterbelts and especially valuable for
        afforestation on irrigated lands. Twenty six crossing combinations of
        this tree were carried out by A.V.Al'benski and his students from
	1933.
        The most successful of these were: white X Bolle (P.alba X
        P. bolleana); pyramidal X Berlin (P. pyramidalis X P. berolinensis);
        pyramidal X Chinese (P. pyramidalis X P. chinensis), Balsam and Berlin
        (P. balsamifera X berolinensis), and Moscow and "krasnonervnyi"
        No. 1191. All of these successfully survived the severe winter of
        1968/1969 and extremely dry summer of 1972, and they had an
        indisputable superiority over the parental species on the basis of
        their morphological features.
        Organization of Forest Seed Production
                Shelterbelt planting in Russia is carried out over a large
        territory with various soil and climatic conditions. On the basis of
        the directions of the breeding work and the organization of the forest
        seed production, three large regions are distinguished:
        1) forest-steppe and chernozem steppe, 2) dry steppe, and
        3) semi-desert.
                The first two regions have concentrated on establishment of
        field shelterbelts and water-regulating forest belts in agricultural
        fields, anti-erosion forest plantations in ravines and gullies and
        afforestation of lands that have a low productivity (sands, waste
        piles, quarries, etc.).
                In the forest-steppe and chernozem steppe regions, which are
        characterized by comparatively good forest growth conditions, it is
        necessary to introduce into the shelterbelt plantations tall trees
	that form open and permeable belts, which exert the best effect on the
        microclimate of the fields. To these belong the pine (Pinus sp.),
	larch(Larix sibirica), oak, birch, Norway maple (Acer platanoides), linden
        (Tillia sp.) and poplar (Populus sp.). Seed plantations of these tree
        species are established with consideration given to the overall
        requirement for protective afforestation. Seed orchards in this region
        are established from progeny of the better local and the tested
        introduced populations. By the establishment of special seed orchards
        there is a more reliable seed supply, a reduction in the damage caused
        by pests and diseases and some improvement in the gene pool of the
	most drought, salt and frost resistant.
                In the dry steppe regions with dark-chestnut soil the belts of
        trees on the fields are mainly oak (Quercus sp.) and their hybrids. On
        chestnut and light-chestnut soils, the best are Siberian elm (Ulmus
        pumila), locust (Robiniapseudo acacia), ash (Fraxinus), hawthorn
        (Crataegus), olive (Elaeagnus) and golden currant (Ribes aureum),
	while on light soils pine (Pinus) is mainly used. The seed plantations are
        also established with consideration given to the overall requirements
        of trees and their function in the region.
                In the semi-desert zone if the country the principal type of
        shelterbelt planting is pasture plantations. For the creation of
        ameliorative plantations of green caponies for relaxation of animals,
        drought and salt resistant shrubs, such as saxaul (Haloxylon),
        "dzhuzgun" (Colligonum) and tamarisk (Tamariz) are utilized.
        Furthermore, in order to improve their productivity, woody foliage
        plants such as winterfat (Eurotia), saltwort (Salsola) and others are
        planted. Seeds are obtained from established seed plantations from a
        quality-controlled gene pool of these species.
        Conclusions
                1. A basic condition for the growing of long-lived shelterbelt
        plantations within the arid treeless zone involves the utilization of
        a particular composition of woody plants, which may be introdused
        species, that are most completely adapted to the soil and climatic
        conditions of a particular geographical locality.
                2. Additional improvement in the resistance of artificial
        plantations may be attained by:
                (a) the plus tree selection of the principal tree species that
                are used for protective afforestation;
                (b) interspecific hybridization of the tree species;
                (c)  the proper selection of the direction of the shelterbelt
                planting (field or pasture-protecting, anti-erosion,
                sand-consolidating, etc.) and the correct organization of the
                silvicultural seed production in different natural conditions
                in the the arid zone.
                3. For the establishment of maternal seed plantations, use is
        made of a genetically valuable gene pool, that is distinguished by an
        elevated resistance to drought, frost, the salt content in the soil,
        pests and diseases.