Tree planting is the process of transplanting tree seedlings, generally for forestry, land reclamation, or landscaping purposes. It differs from the transplantation of larger trees in arboriculture, and from the lower cost but slower and less reliable distribution of tree seeds.
In silviculture the activity is known as reforestation, or afforestation, depending on whether the area being planted has or has not recently been forested. It involves planting seedlings over an area of land where the forest has been harvested or damaged by fire or disease or insects. Tree planting is carried out in many different parts of the world, and strategies may differ widely across nations and regions and among individual reforestation companies. Tree planting is grounded in forest science, and if performed properly can result in the successful regeneration of a deforested area. Reforestation is the commercial logging industry's answer to the large-scale destruction of old growth forests, but a planted forest rarely replicates the biodiversity and complexity of a natural forest.
Because trees remove carbon dioxide from the air as they grow, tree planting can be used as a geoengineering technique to remove CO2 from the atmosphere.
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Most tree planting in Canada is carried out by private reforestation companies.[1] Reforestation companies compete with one another for contracts from logging companies, whose annual allowable cut for the following year is based upon how much money they invest into reforestation and other silvicultural practices. Treeplanting is typically piece work and tree prices can vary widely depending on the difficulty of the terrain and on the winning contract's bid price. As a result, there is a saying among planters: "There is no bad land, only bad contracts." Hard work can yield enough to live on for an entire year for 4 months of hard work, but conditions are brutal.[1]
Tree planting crews often do not permanently reside in the areas where they work, thus much planting is based out of motels or bush camps. Bush camp accommodations usually consist of a mess tent, cook shack, dry goods tent, first aid tent, freshly dug outhouses, and a shower tent or trailer. Planters are responsible for bringing either a tent or car to sleep in. A camp also contains camp cooks and support staff.[1]
Planting is carried out in accordance to the client's specifications, and planters are expected to learn the quality standards for each contract that they work on. Planted clearcuts are spot checked on a regular basis. Although quality concerns vary across contracts, spot checkers are typically looking for such things as: species appropriate site choice, species appropriate spacing, how tight the seedlings are in the ground, how straight the seedlings are, and whether or not the seedlings have been damaged. These concerns vary from region to region, and from contract to contract.
The average British Columbian planter plants 1 600 trees per day[2], but it is not uncommon for veterans to plant up to 4,000 trees per day while working in the interior.[1] These numbers are higher in central and eastern Canada, where the terrain is generally faster, however the price per tree is slightly lower as a result. Average daily totals of 2500 are common, with experienced planters planting upwards of 5000 trees a day. Numbers as high as 7500 a day have been recorded.[1] Planters typically work 8–10 hours per day with an additional 1 to 2 hours of (usually) unpaid traveling time. Work weeks on British Columbian planting contracts are usually 4–5 days long, with 1–2 days off. In Ontario, work weeks are generally 5–6 days long, with 1 day off.
Quite often, tree planting contractors will deduct some of the cost associated with the operation of the contract directly from the tree planter's daily earned wages. These imposed fees typically vary from $10 to $30 per day, and are referred to as "camp costs". In some cases, rookie tree planters end up owing their employer money for the first few pay periods.[3]
Once inflation is factored in, real tree planter earnings have declined for many years in Canada. This has adversely affected the sector's ability to attract and retain workers.[4] Higher wages and much better working conditions in many other industries, from construction, to oil and gas, and even information technology, has led to fewer Canadian young people wanting to plant trees.
Based on statistics for British Columbia, the average tree planter: lifts a cumulative weight of over 1,000 kilograms (2,200 lb), bends more than 200 times per hour, drives the shovel into the ground more than 200 times per hour and travels over 16 kilometres (9.9 mi) with a heavy load, every day of the entire season. The reforestation industry has an average annual injury rate of approximately 22 claims per 100 workers, per year. It is often difficult and sometimes dangerous.[2]
Planting in Britain is commonly referred to as restocking, when it takes place on land that has recently been harvested. When occurring on previously unforested land it is known as new planting.[5] Under the British system, in order to acquire the necessary permissions to clearcut, the landowner must agree a management plan with the Forestry Commission (the regulatory body for all things forestry) which must include proposals for the re-establishment of tree cover on the land. Planting contractors will be engaged by the landowner/management company, a contract drawn up and work will typically take place from November to April when the transplants are dormant.
Planting is part of the rotational nature of much British plantation forestry. Productive tree crops are planted and subsequently clearcut. Some form of soil cultivation may take place and the ground is then restocked. Where the production of timber is a management priority, a prescribed stocking density must be achieved. For coniferous species this will be a minimum of 2500 stems per hectare at year 5 (from planting). Planting at this density has been shown to favour the development of straighter knot-free logs.
Planters are normally paid under piece work terms and an experienced worker will plant around 1500 trees a day under most conditions.
With over 240 million trees planted, Israel is one of only two countries worldwide, that entered the 21st century with a net gain in the number of trees. Due to massive afforestation efforts,[6] this fact echoed in diverse campaigns.[7][8] The various forests of Israel today are mainly the result of a great afforestation campaign by the Jewish National Fund (JNF).[9] Some well-known forests of contemporary Israel, out of the list of forests in Israel, are:
The state of Israel is even afforesting the Negev desert, which accounts for 60% of the country's land mass but remains sparsely populated. In 2006, the JNF signed a 49-year lease agreement with the State of Israel which gives it control over 30,000 hectares of Negev land for the development of forests.[13] The JNF's 600 million dollar Blueprint Negev aims to attract and build infrastructure for 250,000 new settlers in the Negev Desert, to meet the challenge of the massive Jewish immigration from the Soviet Union and Ethiopia.[14] There is a multitude of modern israeli scientific research conducted in the Yair Forest to meet the challenge of climate change, which may result in rapid plant loss and desertification in certain circumstances.[15][16] Studies of the Weizmann Institute of Science, in collaboration with the Desert Research Institute at Sde Boker, have shown that the trees function as a trap for carbon in the air.[17][18] Shade provided by trees planted in the desert also reduces evaporation of the sparse rainfall.[19] The Yatir forest is a part of the NASA project FluxNet, a global network of micrometeorological tower sites used to measure the exchanges of carbon dioxide, water vapor, and energy between terrestrial ecosystem and atmosphere. The Arava Institute for Environmental Studies conducts research at Yatir forest that focuses on crops such as dates and grapes grown in the vicinity of Yatir forest.[20][21] The research is part of a project aimed at introducing new crops into arid and saline zones.[22]
Since 2009, the JNF provided the Arab-Palestinian Authority with 3,000 tree seedlings for a forested area being developed on the edge of the new city of Rawabi, north of Ramallah.[23]
Approximately one thousand smaller forest fires are registered on average every year during the five fire-prone months. Half of them are caused by arson, hostile actions and arab or palestinian terrorists attacs. Ten thousand acres of hand-planted forest were destroyed by Katyusha rockets during the 2006 Lebanon War by Hezbollah militants at the Israeli northern border region. As a response, in summer 2006, JNF launched Operation Northern Renewal, a reforestation effort, which also replaced some topsoil that was burned away.[24] The Mount Carmel forest fire, the largest forest fire in Israel's history, started on December 2, 2010 and burned 41 km2 of forest.
Kaingaroa Forest in New Zealand is the largest planted forest in the southern hemisphere. It is one of the many plantation forests planted since European settlement. The Monterey Pine (Pinus radiata) is commonly used for plantations since a fast growing cultivar suitable for a wide range of conditions has been developed.
Government agencies, environmental organisations and private trusts carry out tree planting for conservation and climate change mitigation. While some work is carried out by private enterprise there are also planting days organised for volunteers. Landcare Research use planted forests for their EBEX21 system for greenhouse gas emissions mitigations.[25]
Trees for the Future is a non-profit organization that plants trees in developing countries to improve land management.[26]
The development of markets for tradeable pollution permits in recent years have opened up a new source of funding for tree planting projects: carbon offsets. The creation of carbon offsets from tree planting projects hinges on the notion that trees help to mitigate climate change by sequestering carbon dioxide as they grow. However, the science linking trees and climate change is largely unsettled, and trees remain a controversial source of offsets.
Climate scientists believe that human-induced global deforestation is responsible for 18-25% of global climate change. The United Nations, World Bank and other leading nongovernmental organizations are encouraging reforestation, avoided deforestation and other projects that encourage tree planting to mitigate the effects of climate change.
Trees sequester carbon through photosynthesis, converting carbon dioxide and water into molecular dioxygen (O2) and plant organic matter, such as carbohydrates (e.g., cellulose). Hence, forests that grow in area or density and thus increase in organic biomass will reduce atmospheric CO2 levels. (Carbon is released as CO2 if a tree or its lumber burns or decays, but as long as the forest is able to grow back at the same rate as its biomass is lost due to oxidation of organic carbon, the net result is carbon neutral.) In their 2001 assessment, the IPCC estimated the potential of biological mitigation options (mainly tree planting) is on the order of 100 Gigatonnes of carbon (cumulative) by 2050, equivalent to about 10% to 20% of projected fossil fuel emissions during that period.[27]
However, the global cooling effect of forests from carbon sequestration is not the only factor to be considered. For example, the planting of new forests may initially release some of the area's existing carbon stores into the atmosphere. Specifically, the conversion of peat bogs into oil palm plantations has made Indonesia the world's third largest producer of greenhouse gases.[28]
Compared to less vegetated lands, forests affect climate in three main ways:
To date, most tree planting offsets strategies have taken only the first effect into account. A study published in December 2005 combined all these effects and found that tropical forestation has a large net cooling effect, because of increased cloudiness and because of high tropical growth and carbon sequestration rates.[29]
Trees grow three times faster in the tropics than in temperate zones; each tree in the rainy tropics removes about 22 kilograms (50 pounds) of carbon dioxide from the atmosphere each year.[30] However, this study found little to no net global cooling from tree planting in temperate climates, where warming due to sunlight absorption by trees counteracts the global cooling effect of carbon sequestration. Furthermore, this study confirmed earlier findings that reforestation of colder regions — where long periods of snow cover, evergreen trees, and slow sequestration rates prevail — probably results in global warming. According to Ken Caldeira, a study co-author from the Carnegie Institution for Science, "To plant forests outside of the tropics to mitigate climate change is a waste of time.".[31]
His premise that grassland reflects more sun, keeping temperatures lower, is, however, applicable only in arid regions. A well-watered lawn, for example, is as green as a tree, but absorbs far less CO2. Deciduous trees also have the advantage of providing shade in the summer and sunlight in the winter; so these trees, when planted close to houses, can be utilized to help increase energy efficiency of these houses.
This study remains controversial and criticized for assuming dark colored trees might replace the frozen, white tundra in the upper northern hemisphere. Regular tree planting projects typically take place on lands that are only slightly different in color. The warming impact was also measured over hundreds of years, rather than a 30-70 year time horizon most climate experts believe we have to fix climate change.
Furthermore, the described warming effect (of temperate and boreal latitude forest) is only apparent once the trees have grown to create a dense 'close canopy', and it is at precisely this point that trees grown for offset purposes should be harvested and their absorbed carbon fixed for the long-term as timber.
While the benefits of tree planting are subject to debate, the costs are low[32] compared to many other mitigation options. The IPCC has concluded that "The mitigation costs through forestry can be quite modest (US$0.1–US$20 / metric ton carbon dioxide) in some tropical developing countries.... The costs of biological mitigation, therefore, are low compared to those of many other alternative measures".[27] The cost effectiveness of tropical reforestation is due not only to growth rate, but also to farmers from tropical developing countries who voluntarily plant and nurture tree species which can improve the productivity of their lands.[33] As little as US$90 will plant 900 trees, enough to annually remove as much carbon dioxide as is annually generated by the fossil-fuel usage of an average United States resident.[34]
The type of tree planted may have great influence on the environmental outcomes. Planting the wrong kind of trees, such as monocultures of eucalyptus where they are not native species, can devastate the lands of the local people. However, it is often much more profitable to outside interests to plant non-native fast-growing trees, such as eucalyptus or pine (e.g., Pinus radiata or Pinus caribaea), even though the environmental and biodiversity benefits of such monoculture plantations are not comparable to native forest, and such offset projects are frequently objects of controversy (see below).
To promote the growth of native ecosystems, many environmentalists advocate only indigenous trees be planted. A practical solution is to plant tough, fast-growing native tree species which begin rebuilding the land. Planting non-invasive trees that assist in the natural return of indigenous species is called "assisted natural regeneration." There are many such species that can be planted, of which about 12 are in widespread use, such as Leucaena leucocephala.[35]