Estonia's Tree of the Year Oak: Why Black Spots Appear on Parquet and How to Remove Them

According to Mari-Liis Mihkelson, director of Puumarket's Tartu branch and Estonia's largest timber retailer, oak, which has been chosen as Estonia's tree of the year this year, is the strongest parquet material, but it should be handled carefully – moisture can create black stains on expensive parquet that are difficult to remove later.

According to Mari-Liis Mihkelson, oak is otherwise a very durable material and a properly maintained oak floor can last a hundred years, but it has one weakness that is worth being aware of. "Oak contains a lot of pigment called tannin, and its reaction with iron compounds in water can turn the wood color black. While ordinary wood typically loses its value when soaked in water, in the case of oak, this material can actually become even stronger. Wood that has been in water for years is called black oak and it is one of the most expensive timber materials in the world," said Mihkelson.

"However, when a stain resembling a burn mark appears at home and in the middle of the parquet, it damages the overall appearance of the floor. Very many people come to the store asking for advice about this problem at the beginning of the year – the bases of Christmas trees tend to leak and people discover the pigment change only weeks later. Leaking flower pots or forgotten floor cleaning equipment also often cause problems," said Mihkelson.

"If oak parquet is mainly a choice between oiled or varnished, the latter is more resistant to both wear and moisture. However, it is also possible to treat oiled floors with a special product to prevent moisture damage. Oak parquet should be regularly oiled once a year anyway," recommended the director of Puumarket's Tartu branch.

"To avoid black stains, spilled water should be quickly removed from the parquet. If damage has already occurred, then often a special chemical product helps, which should be applied to the surface quickly, but if necessary, also sand and re-oil or varnish. Sometimes home insurance can also cover the parquet damage. It's also worth remembering that parquet and furniture made from wood are sensitive to high temperatures, and for example, a hot pot should always have a mat underneath," added Mihkelson.

Estonia's Tree of the Year 2024 – Common Oak

• The oak family (Quercus) belongs to the beech family, and an oak relative is, for example, the chestnut.
• Oaks, which began spreading around the world 45 million years ago, have nearly 500 species that grow in almost the entire northern hemisphere.
• Estonia is the northernmost distribution area of oak; in Finland, oak groves are found only to a small extent in coastal areas due to the colder climate and lack of humus-rich soil.
• The first oak acorns, which are actually nuts, mature only on a 40-year-old tree. A sexually mature oak can produce up to 50,000 acorns per year.
• The felling maturity of oak, which is mainly used in homes as parquet and furniture, is 100-120 years.
• Estonia's thickest and oldest native tree is the nearly 700-year-old Tamme-Lauri oak in Urvastes. However, the age of the Stelmužė oak growing in Lithuania is estimated to be as much as 1,500 – 2,000 years.
• Representing Estonia in the European Tree of the Year 2024 contest is the Viiralt oak growing in Viljandi County, which is known from the engraving "Viljandi Landscape" completed by renowned artist Eduard Viiralt in 1943.