You asked for rules, so here come rules. Specifically, I am referencing the "Правила русской орфографии и пунктуации. Полный академический справочник" (my translation: "Rules of Russian orthography and punctuation. Full academic manual": Правила русской орфографии и пунктуации. Полный академический справочник / Под ред. В.В. Лопатина. — М: Эксмо, 2009. - 480 с.) in its 2009 edition.
But first...
- What is the base form of the word?
It is свежеструган(н)ый.
- Is this an irregular word?
No. Unfortunately, there is no easy way out.
- This is a compound word where
свеж- is an additional root stacked on top of another word. Here is where the rules come in:
§99. В словах с приставкой не-, в сложных словах и в некоторых сочетаниях-повторах формы причастий и прилагательных пишутся так же, как в отдельном (без приставки и не в составе сложного слова или сочетания-повтора) употреблении, т.е. по правилам §98.
With the important part being loosely translated to
§99. In compound words, forms of participles and adjectives are written in the same way, as in a simple usage, i.e., as stated in §98.
So we can move on to analyzing the word струган(н)ый instead.
- So what does §98 state?
Well, the word does not end with −ованный/−ёванный/−еванный, it is not formed from a perfective (NOT TO BE CONFUSED WITH PERFECT) verb, so it leaves us with §98.3:
Причастия не на −ованный (−ёванный, −еванный) глаголов несовершенного вида (они образуются только от бесприставочных глаголов) и соотносительные с ними прилагательные пишутся по-разному: причастия с нн, прилагательные — с одним н.
Or
Participles not ending with −ованный (−ёванный, −еванный) of imperfective verbs (they are formed only from prefixless verbs) and correlative adjectives are written differently: participles with нн, adjectives with a singular н.
So the choice is down to what part of speech it is. And this is the tricky part: in this case, the same form can be an adjective or a participle, depending on the context.
Thankfully, since you have a full sentence, we do have that context. Specifically, §98.3 has a note:
Примечание. Как видно из примеров, причастие опознается по наличию зависимых слов. Бывают, однако, редкие случаи, когда зависимое слово не является признаком причастия.
Or
Note: as you can see from examples (yeah, I didn't mention a whole paragraph of examples in 98.3), the participle is identified by the presence of dependencies. There are, however, some rare cases when the dependent word is not a sign of the participle.
Well, thankfully, in your example, the word has no dependent words, so it is an adjective, so we can finally tell that it has a singular -н-: свежеструганый, or rather свежеструганые.
I bet you thought this would be the end of it? Nope!
So I checked a couple of sources, and what do you know, things are even more complicated.
First of all, you'll notice that most search engines will be really adamant that you have made a typo. In fact, all of my spell-checkers are going crazy: "this word must be written with two н's!"
Wiktionary will yell at you:
Такое написание слова ошибочно! Вы, возможно, имели в виду свежеструганный?
But then I found it: Russian Orthographic Dictionary under editorial supervision of V.Lopatin (В. В. Лопатин Русский орфографический словарь: около 180 000 слов. О.Е. Иванова, В.В. Лопатин (отв. ред.), И.В. Нечаева, Л.К. Чельцова. / Российская академия наук; Институт русского языка им. В.В. Виноградова. — Москва, 2004. 2-е изд., испр. и доп. — М.: 2007.) has an entry:
свежеструганый
свежестр'уганый и свежестр'оганый
(there is an alternative form spelled with an о)
This dictionary is published under Vinogradov's Institute of Russian Language, a subsidiary of the Russian Academy of Sciences, so it is as official as we are going to get. Even the rules that I am using come from a book by the same people. It even references this dictionary in the preface:
Наиболее полным нормативным словарем является в настоящее время академический «Русский орфографический словарь».
The fullest standard dictionary nowadays is the academic "Russian orthographic dictionary".
Also, just to be sure, I also checked Google's Ngram viewer:
Alternatively:
So both forms are clearly present in similar quantities in real texts. But recently, there has been a sharp drop off for seemingly no good reason (other than a mistake being propagated through the interwebs).
So there you have it: the word is spelled with a single -н- and if you use it like this, no one will ever believe you are right :D
