Recent Advances in Energy, Environment and Geology

The Degradation of the Asphalt Alleys by Rhizomes of Herbaceous Plant Species of Couch Grass

FILIPOV Feodor*1, ROBU Teodor**2 1* Soil sciences Department, Faculty of Agriculture 3, Ion Ionescu de la Brad" University of Agricultural Sciences and Veterinary Medicine of Iasi, Mihail Sadoveanu Alley, 700490, Iasi, Romania, +40232407450, [email protected] **2Crop science department, Ion Ionescu de la Brad" University of Agricultural Sciences and Veterinary Medicine of Iasi, Mihail Sadoveanu Alley, 700490, Iasi, Romania, +40232407450, teorobu@uaiasi

Abstract: - The soil cover of urban areas consists of several soil taxonomic units with significantly altered properties and functions. Soils covered by asphalt or another compact materials (such as concrete materials), also known under the name of or ekranic Technosols [1, 2], have strongly modified properties and perform only part of the specific functions that allow only low biological activity and root growth of some plants species. Soil under asphalted alleys have water retention capacity and allows expansion of the roots of woody plants and grasses. The soil horizons under asphalt pavers can be developed only a small number of plant species that are tolerant of deficient aeration. It is well known that the concentration of oxygen decrease considerable and the concentration of carbon dioxide increase significantly (>10% or even 20%) in the compacted soil layers or in the soil layers under asphalt [3, 4]. Some physical soil properties of such as bulk density, compaction degree, air porosity, total soil porosity are substantially modified. Frequentlly, the values of physical properties of soils covered with asphalt indicate that soils are a strong compacted. Under these circumstances the soil covered with asphalt can be explored by a smaller number of plant species. Case studies conducted in several locations of urban area from Romania showed that soils under asphalted paths or alleys keeps some undisturbed soil properties such as particle size, mineralogical composition. Some plants roots may continue to grow after pavement is placed over an existing roots system. Some plants species such as Tillia tomentosa, Populus nigra, Populus alba that grow in the vicinity of asphalted paths lead unevenness, cracking and perforation of asphalt path. Even if it seems impossible, the asphalt path can be traversed by plant roots or runners that develop from buds on roots or rhizomes of herbaceous plant species. One of herbaceous plant species able to penetrate asphalt is Cynodon dactylon known under the name of Couch grass, Bermuda grass, Quickgrass, Twitch grass [5, 6,]. Investigations conducted by us in the field have shown that Cynodon dactylon (perennial grasses) is able to cross paths asphalted by runners that develop from buds on the rhizome. The runners of this plant which grow in soil horizon located under asphalt are able to penetrate the asphalt pavers during the hot summer. In some cases, the first runners cross the pavement in the parallel direction to the surface, at a distance of a few centimeters, after that reach the surface. The developed cracks on the asphalt allow growth of other plant species such as Taraxacum officinale (dandelion), Polygonum aviculare (birdweed, pigweed and lowgrass), Hordeum murinum (wall barley or false barley), Lepidium ruderale (narrow-leaf pepperwort, roadside pepperweed or peppergrass), Poa pratensis (Kentucky Bluegrass, Smooth Meadow-grass, or Common Meadow-grass), Cardaria draba (whitetop or hoary cress). Among the main conclusions drawn from the studies mentioned: (i) Some species of herbaceous perennials such as Cynodon dactylon are able to perforate asphalt. Resistance to penetration asphalted alleys shrinks considerably in hot summer days. (ii) High power crossed the thick rhizomes of couch grass is frequently underestimated and not taken measures to prevent degradation of asphalted alleys. (iii) We believe that highlighting the progressive stages of degradation of asphalt paths and knowledge of biological characteristics of herbaceous plant species able to perforate asphalt are important in the establishment and implementation of preventive measures.

Key-Words: - couch grass, asphalt penetration, ekranic Technosols, flowchart preventing measures.

ISBN: 978-960-474-338-4 136 Recent Advances in Energy, Environment and Geology

1 Introduction typically impermeable urban soil layers into more permeable zones have the potential to increase Asphalt is a constituent of petroleum. All asphalt stormwater infiltration rates [14]. used in the United States is produced by modern oil Our investigation noticed that some plants refineries and is called petroleum asphalt. Petroleum species such as Tillia tomentosa, Populus nigra, asphalt for use in pavements is usually called paving Populus alba, Cerasus avium that grow in the asphalt or asphalt cement to distinguish it from vicinity of asphalted paths lead unevenness, asphalt made for non-paving uses [7]. cracking and perforation of asphalt path (fig 1.1). Asphalt concrete is a composite material commonly used in construction projects such as road surfaces, parking lots, and airports. Asphalt concrete consists of asphalt (used as a binder) mixed with mineral aggregate and then laid down in layers and compacted. The terms "asphalt (or asphaltic) concrete", "bituminous asphalt concrete", and "bituminous mixture" are typically used only in engineering and construction documents and literature. Asphalt concrete pavements are often called just "asphalt" by laypersons who tend to associate the term "concrete" with Portland cement concrete only. The engineering definition of concrete is any composite material composed of mineral aggregate glued together with a binder, whether that binder is Portland cement, asphalt or Fig. 1 Degradation of asphalt path by deformation even epoxy [8]. cracks and perforation under influence of rooting Factors that cause asphalt concrete to deteriorate system of Tillia tomentosa (Foto: F.Filipov, 2007) over time mostly fall into one of three categories: construction quality, environmental factors and traffic loads [7, 8]. Often, damage results from combinations of factors in two or all three categories. Degradation of asphalt pathways in urban areas is noticed by several categories of defects such as deformation cracks, surface texture deficiencies, edge defects, potholes, patches [9]. Environmental factors that cause degradation of asphalted paths are represented by climate, vegetation (various woody and herbaceous plant species), soil properties etc. Numerous studies have revealed that degradation of asphalted paths is amplified by global climate changes were observed the late twentieth century Fig. 2 Degradation of asphalt path by perforation and the beginning of millennium [10, 11,12, 13]. after emergence of Cerasus avium (Foto: F. Filipov, Increase solar radiation, enlargement of temperature 2007) and heat waves, increasing the frequency of increased freeze-thaw cycles (mild winters) Even if it seems impossible, the asphalt path can contribute to degradation of asphalted paths [10]. be traversed by plant roots or runners that develop It well known and recognized that the trees from from buds on roots or rhizomes of herbaceous plant urban spaces greatly improve quality of life for species. One of herbaceous plant species able to human and wildlife by decreasing air temperature in penetrate asphalt is Cynodon dactylon known under the shaded area, by removing carbon dioxide and the name of Couch grass, Bermuda grass, particulates from the air, by interception of rainfall Quickgrass or Twitch grass. direct precipitation into the ground through trunk In this paper is presented progressive stages flow, and take up stormwater through their roots. In of degradation of asphalt paths and biological addition, urban tree roots penetrating through characteristics of herbaceous plant species Cynodon

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dactylon which is able to perforate asphalt. soil covered by asphalt were estimated based on the Establishment and implementation of preventive properties of soil from around studied area. measures is possible only taking into account the Biological and ecological characterization of the biology of plants species Cynodon dactylon was done with obtained data from scientifically publications available in the 2 Problem Formulation library and from the internet. The obtained data, concerning the couch grass, Investigations were conducted in urban areas of from the literature were supplemented with obtained some cities from Romania and another country information in conducted studies in urban spaces. from European Community (fig. 3). Most of the Following the centralization and processing of studies were conducted in urban area of Iasi, located obtained data were elaborated synthetic diagram in the central eastern part of Romania. with ecological requirements and with biological characteristics of couch grass. Data obtained from the literature and from our own studies allowed the development of methods to prevent and limit soil degradation and asphalt alleys. a In developing methods of fighting were taken into b account the biological characteristics of plant requirements to environmental factors and factors that cause degradation of aspalt pavers during the year. Because we did not obtain information on available literature degradation by perforation asphalt walkways through grassy plants, we believe that this work is bringing some original contributions on asphalt degradation by couch grass and the development of effective measures to Fig. 3 Degradation of asphalt path, in Ceske prevent degradation Budejovice, by perforation (b) after emergence (a) of monocotyledonous perennial plants species (Foto: F. Filipov, 2009) 3 Problem Solution

Have been studied sidewalks and paved paths in Establishing methods to prevent degradation the immediate vicinity of roads, in parks and near of asphalted pathways by means of Cynodon the historical monuments. dactylon requires knowledge of the biological Degradation of asphalted alleys after infestation and ecological characteristics. In the following land, in the immediate proximity, with couch grass we present a synthesis of the main biological (Cynodon dactylon) has been studied in the period and ecological features shown in the literature 2007-2012. [5 ,6, 7, 17, 18, 19] and those obtained from In the mentioned period have been taken many own studies. pictures with digital camera and have been collected samples of biological material consisting of young 3.1 Biological specific features of Couch and mature plants of Cynodon dactylon. The obtained images in the field were stored, Grass analyzed and processed on the computer. Biological The main biological specific features of Cynodon collected material was used in order to establish dactylon are presented in figure 1. genus and species of plants. The binomial The main means of propagation or multiplication nomenclature of plant species was done on behalf of of Cynodon dactylon is most vegetative (fig. 4), the rules of the Internation Code for Botanic through the rhizomes (below soil surface) and Nomencature reviewed in the latest taxonomy works stolons (above ground). Stolons and rhizomes are [15, 16]. the stem tissue. Diagnosis and name of the soil was done After the winter, the rhizomes are first vegetative according to new Romanian Sol Taxonomy System organs that will develop new plants. Through known as STRS 2003 [1, 2]. The properties of the rhizome, Cynodon dactylon has opportunity to infest both arable and other lands in large amplitudes of ecological factors.

ISBN: 978-960-474-338-4 138 Recent Advances in Energy, Environment and Geology

3.2 Ecological requirements of Cynodon dactylon Propagation: Quickly infestation of land  vegetative Some specific ecological requirements of (through the rhizomes Period of flowering: Cynodon dactylon to the environmental factors and stolons); spring summer-early are ilustreted in the fig. 4.  many biotypes autumn. infetile;one inflorescence Cynodon dactylon is able to withstand long can produce up to 230 periods of inundation. Cynodon dactylon cannot seeds. withstand conditions of moisture excess, its yield declining as the period of submergence Staggered seed germination: late spring- Exploring soil increases [19]. autumn. resources and degradation of asphalt alleys by Allelopathic substances Intensification resulted in growth period carbohydrate means of perforation and and after decomposition of accumulation after seed organic matter formation fracturing during the hot summer Maintaining viability of High tolerance to rhizome pinholes after inundation dehydration and severe drought period High tolerance to soluble salts Reactivation of pinholes and the development of Maintaining High tolerance to extended new plants from exchangeable rhizomes fragmented infestation of land. sodium Risk factor for High tolerance to degradation of Fig. 4 Diagram with some biological specific severe drought asphalted alleys features of Cynodon dactylon (original, F.Filipov) period

Horowitz found approximately 70% of the High ecological rhizome weight of two and a half year old plants in amplitude of pH the upper 20 cm of the soil and no rhizomes below values (pH=5÷8,5) Growth active period 40 cm [1]. coincides with high The vegetative reproduction ability of Cynodon Thermophile Plant vulnerability of asphalt to dactylon is more rapid compare with seed degradation by Cynodon reproduction. Most biotypes are infertile, and those dactylon on the hot season that are fertile tend to produce small amounts of Fig. 5 Diagram of Cynodon dactylon requirements seeds. Viable seeds can remain viable 3-4 years to the environmental factors under favorable conditions [17]. The seeds remain viable after passing through livestock and after Cynodon dactylon is adapted to a wide range submergence in water for 50 days. Cynodon dactylon biotypes produce inflorescences which of climates. It commonly occurs in regions with range from 5 cm to 40 cm. The sod area is annual rainfall of 400÷800 mm. Optimal proportional to the number of inflorescences with an temperatures range between 35 and 40°C. average of 78 inflorescences per square meter of sod Minimum temperatures for Cynodon dactylon the first year [17, 18, 19]. Seed germination occurs must exceed 10°C. Rhizome growth starts at a in stages from late spring until autumn. After seed temperature higher than 15-20°C. formation, on the November-December period, Rhizomes can survive under considerable intensification of carbohydrate accumulation takes dehydration and after extended of severe place, decreases in late winter and begins increasing drought periods. It can not survive after in late spring. Seasonal rhizome bud germination extended periods with temperatures below does not appear to be correlated with the freezing, or after long period of sun. Rhizomes carbohydrate level [17].

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and roots become dormant at soil temperatures rhizomes have growth oblique or parallel to the below 18ºC. alley surface (fig 8A and 8B).

3.3 The Degradation of the Asphalt Alleys by Rhizomes of Couch Grass Even if it seems impossible, the asphalt path can be traversed by plant roots or runners that develop from buds on roots or rhizomes of couch grass. The land infestation with couch grass caused gradual and continuous degradation of asphalt paths around the historic monument (fig. 6)

Fig. 6 Couch grass caused severe degradation of asphalt paths around the historic monument (foto: F. Filipov, 2012)

Remarkable asphalt punching power by couch Fig 8A&B Degradation of asphalt alleys after grasss grass rhizomes can be seen in fig. 7. growth of couch rhizome on the oblique or parallel direction to the land surface (foto: F. Filipov, 2011)

The developed cracks on the asphalt or small galleries formed as a result breakdown roots of couch grass allow growth of other plant species such as Taraxacum officinale (dandelion), Polygonum aviculare (birdweed, pigweed and lowgrass), Hordeum murinum (wall barley or false barley), Lepidium ruderale (narrow-leaf, pepperwort, f roadside, pepperweed or peppergrass), Poa pratensis (Kentucky Bluegrass, Smooth Meadow- a grass, or Common Meadow-grass), Cardaria draba (whitetop or hoary cress).

3.3 Preventing degradation of asphalt paths by couch grass Fig. 7 Perforation of asphalt pavers by Cynodon dactylon (a)and the fissures (f) formation (foto: Prevention of degradation of the asphalt can be F. Filipov, 2010) achieved by the use of organically or herbicides. Methods to combat couch grasss are shown in After removing asphalt in micro area with slightly Figure 9. elevated and fissured asphalt it was noticed that

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Cynodon dactylon. Research Journal of Plants part are fragmented and Pharmaceutical, Biological and Chemical easilydiseminated and promote Mechanical Sciences formation of new patches The control Volume 3 Issue 2, 2012, pp. 1137 fire of extraterestrial part is not [6] Paul Rita, Mandal Aninda, Datta K. Animesh, eficent Fire An updated overview of Cynodon dactylon (L.) Pers. IJRAP 3(1) 2012 It is efficient if take place in [7] ttp://www.virginiadot.org/business/resources/bu- entire period of plants growth Is Moving/cliping mat-Chapt1AP.pdf-Components of Asphalt practcal when C.d. is small and Concrete. concentration is low Hand labor [8] http://en.wikipedia.org/wiki/Asphalt- Asphalt. [9]http://www.aapaq.org/q/qbspp2012p/docs/Sec16 Non selective erbicide (grass and _Maintenance_Rehabilitationfinal.pdf - Flexible Herbicides weeds killer) applied spring and pavement maintenance and rehabilitation. summer when growth rapidlz [10] Ian Cochran, Climate Report n°18 - Climate Change Vulnerabilities and Adaptation Systemic erbicide: one or two Possibilities for Transport Infrastructures In application could kill the weeds France. (http://www.caissedesdepots.fr/missionclimat) Fig. 9 Methods of preventing of land infestation [11] Boer M & Koster E. (editors) Grenhouse – with couch grass Impact on cold Climate Ecosystems and Landscapes. Catena Supplement 22 4 Conclusion (Cooperating Journal of the International Society 1 Removal by cutting plant couch grass, only in of Soil Science. the interest area on paved paths, will reactivate [12] http://climate.nasa.gov/evidence -Climate pinholes on rhizomes and then determine extending change: How do we know? degradation of paved walkways [13] Willway T., Reeves S.and Baldachin L. 2. Carbohydrate reserves accumulated in Maintaining Pavements in a Changing Climate rhizomes determines the development of vigorous (TRL Limited), www.tsoshop.co.uk, 2008. plants and promotes degradation of asphalted alleys [14] Day, S.D, and S.B. Dickinson (Eds.) 2008. right next. Managing Stormwater for Urban Sustainability 3. Highest favorability ecological factors are using Trees and Structural Soils. Virginia recorded in the summer. After stronger warming, Polytechnic Institute and State University, asphalt becomes more plastic and can be easily Blacksburg, VA. passed by rhizomes and new strains plants. [15] Ciocârlan V. et al. – Flora segetală a 4. Preventing degradation of asphalt alleys by României. Edit. Ceres, Bucureşt,i 2004. means of Cynodon dactylon can only be done by [16] Flora & Vegetatia Moldovei (Romania), Ed. mechanical or chemical removing plant developed Univ. Al. I. Cuza, Iasi, 2006. on both paths and those in areas in close proximity. [17] Horowitz M., Friedman T., Biological activity of subterranean residues of Cynodon dactylon L. References: Sorghum halepense L. and Cyperus rotundus L., [1] Florea N., Munteanu I., 2003 – Romanian 1971. Weed Res., 11, 88–93. System of Soil Taxonomy, Ed. ESTFALIA, [18] Horowitz M., Competitivee effect of three Bucureşti. pp. 142-145 perennial weeds Cynodon dactylon L.(Pers, Cyperus [2] Florea N., Munteanu I., – Romanian System of rotundus L. and Sorghum halepense L Pers., on Soil Taxonomy (in romanian), Ed. ESTFALIA, young citru.J. Horti Science, 1973(48) pp. 135-147. Bucureşti, 2012 pp.151, 152, 155, 156. [19] Horowitz M., Spatial growth of Cynodon [3] Canarache A., Fizica solurilor agricole. Ed. dactylon L. Pers. Weed Res. 12, 1972. pp. 373-383 Ceres Bucuresti, 1990, p 169. [4] Gliman E. F. Tree Root Growth and development. II. Response to Culture, management and planting. J. Environ. Hort. 8(4), 1990 pp. 224 [5] Amrita Asthana, Anil Kumar1, Sumit Gangwar, Jyotsna Dora, Pharmacological Perspectives of

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