Planting seedlings of narrow-leaved ash (Fraxinus angustifolia Vahl) to recover dieback-affected forest stands

U ovom preglednom članku nabrojene su i objašnjene prednosti sadnje krajem ljeta i početkom jeseni kao i proljetne sadnje prije početka vegetacije. Opisano je i s originalnim ilustracijama prikazano nepravilno i pravilno kopanje sadne jame kao i nepravilna i pravilna sadnja sadnica poljskog jasena golog korijena. Objašnjen je utjecaj zbijenosti tla na klijavost sjemena, razvoj klijanca, morfološke značajke nadzemnog i podzemnog dijela sadnica i korijenskog sustava. Raspravlja se o manama kontejnerske proizvodnje šumskih sadnica u čistom organskom mediju poput crnog treseta i nedostacima kod sadnje tako proizvedenih sadnica na terenu. Opisana je i s originalnim ilustracijama prikazana pravilno i nepravilno posađena kontejnerska sadnica poljskog jasena. Prikazana je suvremena tehnologija rasadničke proizvodnje sadnica poljskog jasena u kontejnerima te prednosti pošumljavanja sadnicama obloženog korijena. Kontejnerska proizvodnja je polu automatizirana i sadnja na terenu bi se isključivo trebala obavljati uz pomoć sadilja čije su značajke i prednosti prikazane u članku. Opisana su inovativna rješenja kod konstrukcije sadilja s obzirom na oblik rupe koju rade. Važno da rupe koju rade sadilje ne budu okruglog ili kvadratnog/pravokutnog oblika jer u tom slučaju dolazi do razdvajanja ili pucanja rupe za sadnju od okolnoga tla. Kod sadilja koje rade rupu romboidnog oblika ili iskopane sadne jame, ne dolazi do pucanja po rubu rupe već rupa puca po cijelom profilu što je povoljnije za korijenski sustav biljke. Originalnim ilustracijama su prikazani primjeri loših i dobrog geometrijskog oblika sadne jame. Na primjeru iz rasadnika „Brestje“ u Sesvetama (Hrvatske šume d.o.o.) prikazana je tehnologija rasadničke proizvodnje kontejnerskih sadnica poljskog jasena. Uspoređeni su podaci iz deklaracije supstrata korištenog kod kontejnerske proizvodnje sadnica s rezultatima vlastitih kemijskih analiza istoga u trenutku sadnje sadnica na terenu nakon jedne vegetacije uzgoja. Opisuje se ekstrakcija elemenata iz uzoraka supstrata kao i priprema uzoraka za određivanje sadržaja elemenata u tragovima tehnikom ICP-AES. Prikazani su vrijednosti glavnih parametara supstrata dobivenih tehnikom ICP-AES kao i udjel makro i mikro hranjiva u supstratu. U članku su prikazane glavne morfološke značajke kontejnerskih sadnica poljskog jasena pošumljene na području šumarije Lipovljani u jesen 2017. godine. Posebno je prikazan izgled opranog korijenskog sustava prosječne kontejnerske sadnice i njegova morfološka analiza uz pomoć skenera i softvera WinRHIZO ProLA2400 (2005). Opisani su uzroci velikog mortaliteta sadnica poljskog jasena kod pošumljavanja na području Republike Hrvatske s konkretnim mjerama za poboljšanje sadašnjeg stanja s obzirom na dobre šumarske prakse koje se provode u zemljama srednje Europe i Skandinavije.This review article lists and explains the benefits of planting activities undertaken in late summer and early fall, as well as spring planting before vegetation begins. Both irregular and correct digging of the plant pit and irregular and correct planting of bare-root seedlings of narrow-leaved ash are described and shown with the original illustrations. The influence of soil compaction on seed germination, seedling development, morphological characteristics of the above and below ground part of seedlings and root system is explained. The disadvantages of container production of forest seedlings in pure organic medium such as black peat and the disadvantages of planting seedlings produced in the field are discussed. Properly and incorrectly planted fields of narrow-leaved ash seedlings have been described and shown with the original illustrations. Modern technology of nursery production of narrow-leaved ash seedlings in containers and the benefits of afforestation of seedlings of coated root are presented. Container production is semi-automated and planting in the field should be done exclusively with the help of planters, whose features and advantages are presented in the article. Innovative solutions for the construction of a planter are described with regard to the shape of the hole that they make. It is important that the holes made by the planters are not round or square / rectangular, otherwise the planting holes will break or burst away from the surrounding soil. In the case of planters operating a rhombus-shaped hole or dug-in planting pit, there is no cracking at the edge of the hole, but the hole shoots all over the profile, which is more favorable to the root system of the plant. The original illustrations show examples of poor and good geometric shapes of a plant pit. An example taken from the Brestje nursery in Sesvete (Croatian Forests Ltd.) is used to illustrate the technology of nursery production of container seedlings of narrow-leaved ash. The data from the substrate declaration used in container production of seedlings were compared with the results of our own chemical analyzes at the time of planting the seedlings in the field after one growing vegetation. The extraction of elements from the substrate samples is described and so is the preparation of samples for trace element content determination by the ICP-AES technique. The values ​​of the main substrate parameters obtained by the ICP-AES technique are presented, as well as the content of macro and micro nutrients in the substrate. The article presents the main morphological characteristics of container seedlings of narrow-leaved ash planted in the Lipovljani forest area in autumn 2017. In particular, the appearance of the washed root system of an average container seedling and its morphological analysis by means of WinRHIZO ProLA2400 (2005) scanner and software are presented. The causes of high mortality of narrow-leaved ash seedlings during afforestation in the Republic of Croatia are described, and concrete measures are proposed to improve the current situation in line with good forestry practices implemented in the countries of Central Europe and Scandinavia